H1N1 Mutates in India

Mar 22, 2015 | Colleen Nguyen | Outbreak News

According to researchers at Massachusetts Institute of Technology (MIT), samples of the H1N1 swine flu strain currently ravaging India indicate that the strain may have mutated to become more infectious and dangerous [1]. As of March 15th, the country’s Ministry of Health estimates there to be 29,938 cases of swine flu across India, resulting in 1,731 deaths [2]. These figures surpass the country’s H1N1 numbers from the 2009 pandemic, in which 27,236 cases and 981 deaths were reported [2].

Published earlier this month in an issue of Cell Host and Microbe, researchers Kannan Tharakaraman and Ram Sasisekharanan suggest that an evolution of the hemagglutinin (HA) protein -- which encompasses “receptor binding, fusion, and transmission properties” -- has taken place, resulting in a more virulent strain of the pandemic H1N1 virus, as well as increased disease severity among current flu cases in India [1]. This is because one of the specific mutations can be linked to “increased severity of the disease, while another enhances its infectiousness” [4]. The mutations, alongside ideal environmental conditions such as high population density -- allowing for easier transmission -- has permitted the virus to become entrenched within the population [3]. According to Dr. Nicole Iovine, an infectious disease physician from the University of Florida, a majority of Indians do not get their flu vaccinations either [5].

What’s often concerning about this strain of swine flu in particular is its tendency to target young adults [5]. While flu typically strikes children and elderly populations the hardest, this year’s H1N1 strain has shown to impact young adults the most. This is the same infection pattern as the 2009 and 1918 H1N1 pandemics [5]. In their commentary, Tharakaraman and Sasisekharana call for increased influenza surveillance and monitoring, to allow for further examination of the mutation of the influenza virus and its implications [3].

Contrary to the recently published research on the topic, India’s National Institute of Virology claims that the swine flu virus strain currently causing the outbreak in the country is the same strain from the 2009 H1N1 pandemic and that the strain has not mutated [1].

 

Sources

[1] http://www.washingtonpost.com/world/asia_pacific/study-indias-swine-flu-virus-may-have-mutated-into-more-dangerous-strain/2015/03/12/bdf8a11f-934f-4991-ba42-c2be7dd23748_story.html

[2] http://timesofindia.indiatimes.com/india/Indias-swine-flu-toll-climbs-to-1731-number-of-cases-touches-30000/articleshow/46583897.cms

[3] http://www.cell.com/cell-host-microbe/abstract/S1931-3128%2815%2900076-1

[4] http://time.com/3741736/swine-flu-h1n1-india-virus-mutation-study/

[5] http://www.forbes.com/sites/fayeflam/2015/03/12/as-deadly-h1n1-spreads-in-india-scientists-find-worrisome-new-mutations/

 

Blinding Syphilis: West Coast Cases Rise

Mar 20, 2015 | Noushin Berdjis | Outbreak News

Recently, the west coast has seen an unusual increase in ocular syphilis cases. Since December 2014, there have been 14 confirmed cases and two suspected cases of this rare disease [1-3,5-6].  Eight of the confirmed cases were in individuals also infected with HIV, five of the cases were among men who have sex with men, and two of the cases have already resulted in blindness [1-3]. The confirmed cases occurred in Washington state and San Francisco, California. Los Angeles County is currently investigating the two suspected cases that were reported to the Department of Public Health on Tuesday, March 10th [3].

 

What is Ocular Syphilis?

Syphilis is a sexually transmitted disease (STD) caused by the bacteria, Treponema palidium [5].  A syphilis infection occurs as the result of direct contact with a syphilis sore called a ‘chancre’, which can be present on the external genitals, anus, rectum, as well as the inner mouth and lips of an infected individual [4].  Once infected, syphilis can be spread by person-to-person transmission during vaginal, anal or oral sex [4]. The disease has been classified in the following stages: primary, secondary, and latent syphilis. Primary syphilis consists of the appearance of a single or multiple, painless syphilis sores, while secondary syphilis consists of the appearance of a skin rash and mucous membrane lesions. Latent syphilis can occur if the disease has been left untreated [4]. These individuals are generally asymptomatic for years, but the disease can ultimately damage the internal organs and brain, and cause death [4].

Ocular syphilis can develop as a complication of primary or secondary syphilis that has been left untreated, and can cause blindness [1-3,5]. Symptoms of ocular syphilis include red eyes, inflammation, eye pain, blurred vision, light sensitivity, sudden loss of vision, and seeing floating spots [5,6].

 

The Importance of Screening

As a result of this outbreak, public health officials have been encouraging health care providers - particularly primary care doctors and optometrists - to be cognizant of patients showing symptoms associated with ocular syphilis [1-3,5]. Syphilis is easy to cure with penicillin if detected in the early stages of the disease. However, despite the availability of antibiotics and continuous public health interventions, syphilis remains a common infection within the United States [4]. A steady increase in the rate of infections has been noted since 2000, with the majority of infections occurring among men who have sex with men, and concurrent in individuals infected with HIV [4].  In 2013, California had the second highest rate of syphilis infections in the nation, following Georgia [1]. This increase in ocular syphilis cases has highlighted the importance of regular STD screening exams for all sexually active individuals, but especially those who are at an increased risk [1-3]. Additionally, public health campaigns should focus on the importance of condom use to help stop the spread of this sexually transmitted disease.

 

Sources

  1. http://www.latimes.com/local/lanow/la-me-ln-blinding-syphilis-los-angeles-aids-healthcare-foundation-20150310-story.html
  2. http://www.sfcityclinic.org/Ocular%20Syphilis%20Advisory_2.20.15.pdf
  3. http://www.ibtimes.com/blinding-cases-syphilis-west-coast-prompt-health-alert-la-county-1843078
  4. http://www.cdc.gov/std/syphilis/
  5. http://www.philly.com/philly/health/Cases_of_ocular_syphilis_on_the_rise.html
  6. http://sanfrancisco.cbslocal.com/2015/03/11/cases-of-ocular-syphilis-in-san-francisco-and-other-west-coast-cities-increasing/
Pakistan & Polio

Mar 8, 2015 | Colleen Nguyen | Outbreak News

In recent weeks, police in Pakistan have arrested hundreds of parents for refusing to vaccinate their children from polio [1]. In the northwestern province of Khyber-Pakhtunkhwa, the police issued warrants for 13,000 to 16,000 refusal cases [2]. According to one official, 471 people had been arrested in the city of Peshawar alone [1]. Police officials are exercising this action under a Pakistan law against endangering public safety [1]. While arrests have been made in the past, they have been few and far in between. This recent mass crackdown on vaccination refusal is being done in an effort to end the polio crisis that has plagued Pakistan, for good [2].

 

All About Polio

Poliomyelitis, otherwise known as polio, is caused by poliovirus [3]. There are two strains of poliovirus currently circulating -- wild poliovirus Type 1 and vaccine-derived poliovirus [15]. Highly contagious, polio is spread through person-to-person contact via the fecal-oral route [3]. Once internal, polio lives in a person’s throat and intestines, waiting to be shed [3]. Infected people can shed the virus from a few days before the onset of symptoms to almost two weeks after they appear [3].

The virus affects mostly those under five years of age [4]. Approximately 72% of those who become infected with polio are asymptomatic [3]. However, in about 25% of those who are infected, flu-like symptoms appear, including: fever, sore throat, fatigue, nausea, and stomach pain [3]. These flu-like symptoms often last two to five days, before resolving on their own [3]. According to the World Health Organization (WHO), one in two hundred polio infections leads to irreversible paralysis -- the virus can invade and infect a person’s brain, causing spinal damage and paralysis [3, 4]. Among those with paralysis, about 10-20% die due to immobilization of lung muscles [4].

 

The Battle Against Polio

Since 1988, polio cases around the world have drastically dropped by 99% -- from 350,000 cases spread across 125 countries in 1988, to only 416 cases globally in 2013 [4]. At the end of 2014, Pakistan was one of only three countries that remained polio-endemic (the others were Nigeria and Afghanistan) [4]. There were 306 polio cases accounted for in the country last year -- the leading number globally, with thirteen cases thus far in 2015 [6]. Regions such as the Federally Administered Tribal Areas (FATA) and Khyber-Pakhtunkhwa are where polio remains most entrenched and where transmission is most intense [5].

Since 1978, routine immunization against polio has been mandatory in the country; but, according to a recent vaccine coverage survey, WHO-UNICEF approximates that only 66% of the country has been fully immunized [7]. To be considered fully immunized, an individual must receive a “primary series of at least three doses of inactivated poliovirus vaccine (IPV), live oral poliovirus vaccine (OPV), or four doses of any combination of IPV and OPV”[8]. National Immunization Days, during which mass vaccination occurs, have been pushed over recent years. These activities are held as complementary to routine immunization and as only a strategy meant to interrupt the circulation of poliovirus through blanket coverage of eligible children [9].

 

Defying the History of Violence

What has kept Pakistan from eliminating polio for good? In 2012, the Pakistani Taliban banned polio immunization. As a result, efforts to vaccinate in Taliban-controlled regions have halted, and has led to the deaths of more than 60 polio fieldworkers [10]. Threats of violence from the Taliban extend beyond vaccinators and also include parents who allow for the polio immunization of their children [10]. The Taliban’s oppositional stance arose as a response to the United States Central Intelligence Agency’s (CIA) pursuit of Osama Bin Laden [10]. In an attempt to lure and confirm Bin Laden’s whereabouts, the intelligence agency set up a fake hepatitis vaccination campaign in Abbottabad, Pakistan [10]. Before the Taliban’s vaccination ban in 2012, Pakistan was on track to eliminating polio. According to Mufti Muneeb Ur Rehman, a moderate cleric in Pakistan, the resurgence of polio in Pakistan is a direct result of the CIA’s conduct [10]. Other militant oppositionists believe that the polio vaccines are a conspiracy to “spoil” Muslim children -- a reference to rumors that the vaccine causes infertility [13]. The consequences of these actions and beliefs reverberate today.

On February 13, 2015, a polio vaccination team disappeared after working in the southwestern town of Zhob, located in the province of Balochistan [11]. As with most typical polio field teams targeted, the kidnapped included two vaccine workers, two security personnel, and a driver [11]. Four days after their abduction -- the team was found murdered, assumingly seized and executed by Taliban militants [12].

However, in the town of Karachi, defiance against the Taliban’s murderous campaign provides a glimmer of hope in the long standing battle against the disease. In fact, recruitment for polio workers has not been a problem for the city, which boasts a population of more than 20 million [13]. Shahnaz Wazir Ali, provincial coordinator for public health in Sindh province, attributes this to “continuous engagement with the workers and constant direction with local government officials” [13]. Others distinguish the polio worker’s salary as a motive to enlist in the cause, despite known security risks [13].

 

The Eradication Initiative

The organization Rotary International began spearheading polio eradication efforts in 1985 [14]. It is responsible for an estimated vaccination of 2 billion children across 122 countries and their efforts have been in collaboration with other prominent organizations such as the Gates Foundation, UNICEF, and WHO [14].

Prior to intense opposition and even in the midst of current violence, Rotary has implemented simple strategies such as village-to-village and door-to-door vaccination to battle polio in Pakistan [14]. The group has also distributed cell phones among community health workers -- particularly, midwives -- who canvass areas to aid in surveillance and tracking of unvaccinated children and pregnant mothers, especially difficult for villages located primarily off the grid [14]. The cell phones provided allow for data to be collected and later uploaded to a central source [14]. Other efforts to eradicate polio include a collaboration with the Coca-Cola company, to build a reverse-osmosis water plant, within the city of Karachi -- this helps to curb the spread of polio through the provision of clean water [14].

There exists vaccines for the prevention of polio, but no cure. To fulfill the goal of polio eradication, the effort must overcome underlying government suspicion, factionalism, and an ever-growing world of inequality. For the idealists, therein lies the perfect challenge.

 

 

Sources

[1] http://www.washingtontimes.com/news/2015/mar/2/pakistan-police-arrest-parents-refusing-kids-polio/

[2] https://foreignpolicy.com/2015/03/02/pakistan-issues-warrants-over-polio-vaccination-refusals-indias-budget-intended-to-boost-growth-avalanches-continue-in-afghanistan/

[3] http://www.cdc.gov/polio/about/

[4] http://www.who.int/mediacentre/factsheets/fs114/en/

[5] http://www.polioeradication.org/Infectedcountries/Pakistan.aspx

[6] http://www.emro.who.int/polio/countries/pakistan.html

[7] http://apps.who.int/immunization_monitoring/globalsummary/countries?countrycriteria%5Bcountry%5D%5B%5D=PAK

[8] http://www.cdc.gov/vaccines/vpd-vac/polio/

[9] http://www.polioeradication.org/Aboutus/Strategy/Supplementaryimmunization.aspx

[10] http://www.npr.org/blogs/goatsandsoda/2014/07/28/330767266/taliban-in-pakistan-derails-world-polio-eradication

[11] http://www.voanews.com/content/violence-plagues-polio-vaccination-teams-in-pakistan/2644052.html

[12] http://www.bbc.com/news/world-asia-31507217

[13] http://www.theguardian.com/global-development/2015/feb/02/karachi-polio-workers-pakistan-militants

[14] http://time.com/3051398/polio-pakistan-rotary/

[15] http://www.who.int/biologicals/areas/vaccines/poliomyelitis/en/

New Aggressive HIV Strain Found in Cuba

Mar 1, 2015 | Colleen Nguyen | Outbreak News

A new and aggressive strain of HIV, which can develop into AIDS within three years of infection, has been discovered in Cuba [1]. Researchers raise concerns that the strain’s accelerated progression is so rapid, that antiretroviral treatment may come too late [1]. The study came in response to Cuban clinicians reporting an ‘increasing trend’ of rapid progression AIDS cases in Cuba and results were recently published in EBioMedicine on January 28, 2015 [1,2].
 

About HIV and AIDS

As the world’s leading infectious killer, ‘HIV’ stands for Human Immunodeficiency Virus. HIV attacks a person’s immune system, destroying what the body needs to fight off disease and infection [4,6]. The virus is transmitted through bodily fluids such as blood, semen, and breast milk and these fluids must come into contact with the mucous membrane, damaged tissue, or injected directly into a person’s bloodstream, in order for transmission to occur [8]. Some of the earliest  symptoms of HIV infection include: fever, swollen glands, sore throat, fatigue, and rash [7]. However, many who are HIV positive may not immediately look or feel sick. During this stage -- clinical latency -- HIV reproduces at low levels, though remains very active within a person’s body [7]. Treatments such as antiretroviral therapy (ART) have successfully helped manage HIV symptoms and has prolonged lives [7].

Over time, HIV can develop into AIDS -- Acquired Immunodeficiency Syndrome -- which is considered to be the final stage of HIV infection [4]. While not everyone reaches the AIDS stage, those who do often have a certain number of opportunistic infections, cancer, or a low CD-4 cell count. It is the onset of these symptoms that indicates that the infected person has transitioned from the clinical latency stage to AIDS [4].

 

The Cuban Strain - CRF19

Typically, it takes HIV infection without treatment approximately five to ten years to advance to AIDS. Among patients included in the study in Cuba, the strain advanced significantly faster. According to the study, it was found that patients with the mutated strain developed AIDS within three years [1,2]. It is important to note that rapid progression of HIV to AIDS does happen -- individuals who contract HIV with an already suppressed immune system can have faster advancement to AIDS [3]. That said, it is often a patient’s pre-existing immune system differences and not the HIV-subtype that contributes to AIDS development. However, in this study, the HIV variant seemed to play an imperative role in the rapid advancement [3].

Upon closer inspection, researchers found that the rapidly-advancing HIV patients were linked by their variant type of HIV. The new, variant-HIV was found to be a new recombinant subtype consisting of sub-types A, D, and G [3]. This new combination has been named CRF19 [3].

A researcher on the study, Prof. Anne-Mieke Vandamme of Belgium University-Leuven, further explains how this particular variant accelerates the AIDS process:

“There are two types of co-receptors that HIV can use: CCR5 or CXCR4. And in the normal progression of the HIV to AIDS it often happens that the virus switches co-receptor. It almost always starts with using CCR5 and then it switches to CXCR4 after many years. And once it switches the progression to AIDS goes very fast” [3].  

Researchers also suspect that the inclusion of sub-type D may also be the key in the aggressiveness of the CRF19 strain. HIV sub-type D “contains an enzyme that enables HIV to reproduce in greater numbers – and it takes proteins from other subtypes and uses them in new virus particles” [3].
 

The Burden of HIV/AIDS

On a global scale, 35 million people worldwide are currently living with HIV/AIDS [6]. The greatest burden of the disease lies within low and middle income countries, specifically within sub-Saharan Africa [6]. According to UNAIDS, there is approximately 16,000 people in Cuba currently living with HIV/AIDS [9]. Of those infected, about 15,000 are adults aged 15 years and older [9].

More than 1.2 million people are currently living with HIV in the United States and 1 in 7 people do not know that they are infected [5]. Approximately 25% of those who are acquiring new infections in the United States are between the ages of 13 and 24 years old -- those in this demographic also are usually unaware that they are infected and may pass on the virus to others unknowingly, perpetuating the transmission cycle [5].

 

 

 

Sources

[1] http://www.upi.com/Health_News/2015/02/14/Aggressive-new-HIV-strain-detected-in-Cuba/2421423945549/

[2] http://www.sciencedirect.com/science/article/pii/S2352396415000389

[3] http://www.voanews.com/content/aggressive-hiv-cuba-13feb15/2643090.html

[4] https://www.aids.gov/hiv-aids-basics/hiv-aids-101/what-is-hiv-aids/

[5] https://www.aids.gov/hiv-aids-basics/hiv-aids-101/statistics/index.html

[6] https://www.aids.gov/hiv-aids-basics/hiv-aids-101/global-statistics/index.html

[7] https://www.aids.gov/hiv-aids-basics/hiv-aids-101/signs-and-symptoms/index.html

[8] http://www.cdc.gov/hiv/basics/transmission.html

[9] http://www.unaids.org/en/regionscountries/countries/cuba

 

“Superbug” Outbreak at UCLA Medical Center

Feb 27, 2015 | Noushin Berdjis | Outbreak News

A recent outbreak of the “superbug”, carbapenem-resistant Enterobacteriaceae (CRE) bacteria, at the Ronald Reagan UCLA Medical Center has resulted in seven confirmed infections and two deaths [2]. The source of the outbreak was found to be two of the hospital’s seven Olympus Corp. duodenoscopes that were used between October 3 and January 28 [2]. A total of 179 patients have been exposed [1,2]. The UCLA Medical Center is providing these individuals with free, at-home screening tests to determine if they are infected with the CRE bacteria as a result of their exposure [2].

What is CRE?

Carbapenem-resistant Enterobacteriaceae bacteria are part of a family of bacteria commonly found in the colon. Over time, some of these gut-dwelling pathogens have developed high-resistance against many widely used antibiotics. These bacteria contain an enzyme that breaks down carbapenem antibiotics, rendering them useless, and making it very difficult to treat patients with CRE infections. Antibiotic-resistance has become an increasing public health problem across the globe. CRE is particularly dangerous because the bacteria are able to resist “last defense” antibiotics.  

Healthy individuals are generally not at risk for CRE. Infections are most common in nursing homes and hospitals, where invasive devices such as ventilators, urinary catheters, and intravenous catheters, result in exposure to CRE.

How Did This Outbreak Happen?

Duodenoscopes are a type of endoscope used to obtain material for a biopsy, treat gallstones and cancers, as well as other digestive disorders [3]. The scope consists of flexible tubes, which are inserted into the mouth, threaded through the throat, stomach and into the small intestine [3]. Although fairly non-invasive compared to surgery, this procedure allows for easy contamination of the devices with pathogens, such as CRE. Contaminated scopes are then able to transmit the pathogen from patient to patient [4,5]

The UCLA Medical Center duodenoscopes were cleaned according to both FDA and manufacturer guidelines, therefore the outbreak has not been traced to a break in protocol [1]. Due to their structure and mechanics, these devices are difficult to clean. Duodenoscopes cannot be autoclaved, like a scalpel would be, because their lenses and electronics make them sensitive to high temperatures [1]. Instead, the scopes are cleaned by hand with liquid disinfectants [1]. These procedures are not sufficient to completely remove CRE bacteria, which can then colonize on the device [2].

What's Being Done?

Following this outbreak, the UCLA Medical Center has removed the two contaminated duodenoscopes and implemented a more stringent decontamination process for the remaining devices [2]. In addition to the FDA and manufacturer cleaning guidelines, automated machines are now used for disinfection, and the devices will now be receiving off-site sterilization using ethylene oxide gas [2].  

This outbreak is not unprecedented. Since 2012 there have been CRE outbreaks in Illinois, Pennsylvania and Washington [5]. Furthermore, duodenoscopes are often the source of disease transmission [5]. Thus hospitals are encouraged to re-evaluate their sterilization procedures, and consumer advocates are calling for greater disclosure to patients undergoing procedures that put them at risk for infection [5].
 

 

Sources:

[1] http://www.bloomberg.com/news/articles/2015-02-20/the-l-a-superbug-outbreak-five-things-you-should-know

[2] https://www.uclahealth.org/news/ucla-statement-on-notification-of-patients-regarding-endoscopic-procedures

[3] http://www.fda.gov/MedicalDevices/Safety/AlertsandNotices/ucm434871.htm

[4] http://www.cdc.gov/HAI/organisms/cre/

[5] http://www.latimes.com/business/la-fi-hospital-infections-20150218-story.html#page=1

[6] http://www.latimes.com/science/sciencenow/la-sci-sn-cre-outbreak-carbapenem-resistant-enterobacteriaceae-20150218-story.html

Hybrid 'Super' Mosquito Reported in Mali

Feb 22, 2015 | Colleen Nguyen | Research & Policy

Two types of malaria-transmitting mosquitoes in Mali -- Anopheles gambiae and Anopheles coluzzii -- have interbred to create a new hybrid “super” mosquito resistant to insecticide treated bed nets [1]. A recent publication in the Proceedings of the National Academy of Sciences, provides convincing evidence that man-made changes in the environment -- in particular, the introduction of insecticides -- have impacted the mosquito’s evolutionary relationship and has removed the “reproductive isolation that separates them” [2]. Prof. Gregory Lanzaro -- a medical entomologist and professor at the University of California, Davis -- the leader of the study’s research group, states that the results of the study is “an example of one unusual mechanism that has promoted the rapid evolution of insecticide resistance in one of the major malaria mosquito species” [2]. Given the recent findings, there may be a few implications regarding its impact on malaria, particularly in endemic areas.

What are the Implications?

Malaria, a mosquito-borne disease caused by a parasite, impacts mostly developing tropical and subtropical areas of the world [3]. According to the Center for Disease Control (CDC), approximately 627,000 people died from malaria in 2012, with the majority being young children in sub-Saharan Africa [3]. Young children are the most vulnerable to malaria, because they have yet to develop immunity to the disease [3]. Additionally, pregnant women are also vulnerable, because their immunity decreases as a result of their pregnancy [3].

Malaria-control efforts have curbed the disease’s impact, cutting mortality by 45% and saving 3.3 million lives globally [3]. The most common preventive measures include indoor residual spraying (IRS), vector control, anti-malarials, and insecticide-treated bed nets (ITNs) [4]. It has been shown in community-wide trials across Africa that ITNs can reduce child mortality from all diseases by 20% [4]. An estimated 214 million long-lasting ITNs were distributed to malaria countries across Africa in 2014 -- this has brought the distributed regional total to 427 million long-lasting ITNs since 2012 [5].

With the introduction of a new hybrid species of mosquito that is resistant to ITNs, the impact that ITNs have had in the battle against malaria may truly be a figment of the past. This issue will only get worse if left unaddressed. Mosquito insecticide resistance isn’t novel. According to the WHO, 49 countries reported mosquito resistance to at least one insecticide between 2010 and 2013, and the number seems to be growing [5]. Prof. Lanzaro reports that, "it has reached a level at some localities in Africa where it is resulting in the failure of the nets to provide meaningful control, and it is my opinion that this will increase" [2]. Without new means to combat insecticide resistance, a rise in mosquito-borne diseases such as malaria, is imminent.

 

Sources

[1] http://blogs.ucdavis.edu/egghead/2015/01/09/hybrid-super-mosquito-resistant-to-insecticide-treated-bed-nets/

[2] http://www.medicalnewstoday.com/articles/287907.php

[3] http://www.cdc.gov/malaria/malaria_worldwide/index.html

[4] http://www.cdc.gov/malaria/malaria_worldwide/reduction/itn.html

[5] http://www.who.int/malaria/media/world_malaria_report_2014/en/

The Rise of Avian Influenza

Feb 20, 2015 | Kerri Lipton Colleen Nguyen | Outbreak News

The Outbreak

Since mid-December 2014, several cases of highly pathogenic avian influenza (HPAI) have been reported in birds in the Pacific Northwest United States, including Washington, Oregon, Idaho, Utah and California (1). The avian influenza (AI) strains detected, include: H5N2, H5N8 and even one case of H5N1. The H and N refer to hemagluttin and neuraminidase, respectively, and are proteins expressed by the virus that are used to identify different strains of influenza (2). Afflicted birds include captive wild birds, wild aquatic birds, and backyard poultry (1). All birds in the backyard flocks with reported infections were culled (3). Most AI strains are not known to infect humans, but some that do (including H5N1) can be very serious and potentially life-threatening.
 

What It Means for US Poultry

Large outbreaks of AI do not often occur in the United States. Although there is a fear of potential spillover of AI strains from birds to humans, there is a more imminent risk of economic loss due to AI infections. Although there has been only one report of AI infection in a U.S. commercial flock, the entire industry suffers (4). As of January 7th, 2015, at least 30 countries have implemented restrictions on the importation of US poultry, including a ban on poultry from Oregon and Washington (3). Thailand, South Korea, and Sri Lanka, have gone as far to ban all US poultry and poultry products (3).

AI Clinical Signs

Avian influenza can sometimes have no clinical signs in poultry. In low pathogenic avian influenza (LPAI), some clinical signs include coughing, sneezing and nasal discharge. Morbidity and mortality are usually low in LPAI strains. Some clinical signs that can manifest in HPAI include: cyanosis (blue coloration of skin and membranes due to low oxygen) and edema (swelling from fluid build-up) of head, comb, waddle and other exterior body parts, greenish diarrhea, and bloody ocular or nasal discharge (5).

Commentary

Although there has not yet been a human case of H5N8 or H5N2, it is important to take precautions when in close contact with backyard birds. Currently, H5N8 and H5N2 are not known to infect humans. Given the ever-changing nature of influenza viruses, it is possible that someday H5N8 and H5N2 can jump to humans, just as H5N1 did. If you are an owner of backyard poultry, it is important to keep your birds vaccinated to prevent infection of avian influenza and to report any clinical signs to your state’s Department of Agriculture.   

 

Sources

[1] http://www.cdc.gov/mmwr/preview/mmwrhtml/mm6404a9.htm?s_cid=mm6404a9_w

[2] http://www.capitalpress.com/Nation_World/Nation/20150212/animal-health-officials-rush-to-curb-spread-of-bird-flu-virus

[3] http://www.politico.com/story/2015/01/avian-flu-united-states-poultry-114046.html

[4] http://www.capitalpress.com/20150126/bird-flu-hits-first-us-commercial-poultry-flock

[5] http://www.merckmanuals.com/vet/poultry/avian_influenza/overview_of_avian_influenza.html

Measles in America: Why vaccination matters

Feb 18, 2015 | Maia Majumder | Outbreak News

The 2015 Disneyland measles outbreak in the United States, which started in late December and spread to more than 100 people in just 6 weeks, has recently become the subject of substantial media scrutiny. Measles is extremely infectious, exhibiting a basic reproductive number between 12 and 18 - one of the highest recorded in history. This means that for every 1 case who gets sick in a totally susceptible population, 12 to 18 other folks get sick, too. Thankfully, when uptake of the measles vaccine is high enough in a given community, it's almost impossible for the disease to spread - thus halting a potential outbreak in its tracks.

But what happens when vaccine rates aren't high enough? Given the growing anti-vaccination movement in the United States, our team at HealthMap took on the task of responding to this very question by developing an interactive visualization that allows users to explore the impact of different vaccination rates on a simulated measles outbreak.

Clearly, the lower vaccination rates are among exposed populations, the larger potential outbreaks can become - and even rates as high as 80% aren't high enough to prevent sustained transmission. The bottom line? Vaccines really do matter - and it's important for those of us who are healthy enough to get vaccinated to do our part!

Guinea Worm - How Close Are We to Eradication?

Feb 11, 2015 | Noushin Berdjis | Outbreak News

Disease Control, Elimination, and Eradication

Smallpox and rinderpest are two infectious diseases that have been successfully eradicated. Smallpox was eradicated in 1980 and rinderpest in 2011 [1,2]. Will Guinea Worm be the next disease to be eradicated? To fully understand disease eradication, it is important to comprehend the concepts of disease control, elimination, and eradication.

Disease control is defined as the “reduction of incidence, prevalence, morbidity or mortality to a locally acceptable level as a result of deliberate efforts” [3]. This requires the continuous use of interventions to maintain disease incidence. Disease elimination has been defined as the “reduction to zero incidence in a defined geographical area” [3]. Disease elimination also requires the continued implementation of control measures to prevent the re-establishment of the disease. Finally, disease eradication is defined as the “permanent reduction to zero of worldwide incidence [of disease]” [3]. The key difference between elimination and eradication is that elimination is limited to a specific geographic location, such as a country, while eradication means the disease has been eliminated throughout the entire world. Therefore elimination is required before a disease can be eradicated.

 

Guinea Worm

Guinea Worm Disease, also known as Dracunculiasis, is a highly debilitating, waterborne disease caused by the parasitic worm, Dracunculus medinensis [4]. Infection occurs when an individual drinks water contaminated with Dracunculus medinensis larvae (housed within minute crustacean copepods). Following ingestion, the larvae migrate through the intestinal wall and mature.  After full maturation has been reached (approximately 1 year after ingestion), the female worm migrates to the subcutaneous tissue and is slowly expelled through a blister, usually located on the lower leg [4]. This blister is very painful, therefore infected individuals often immerse their foot in a local body of water to alleviate the burning sensation. Once immersed in water the blister ruptures and releases larvae, thus continuing the transmission cycle [4].

Control efforts include mapping endemic villages, establishing surveillance and case containment (to prevent individuals from contaminating local drinking water sources), implementing interventions aimed at increasing access to safe drinking water, waterborne (?) vector control through larvicides, as well as health education and community-involvement [7,8].  

So how close are we to eradication? The answer is, very close. The incidence of Guinea Worm Disease has been reduced by 99.9% [8].

Since the launch of global eradication campaigns, lead by The Carter Center, the World Health Organization and UNICEF, the number of Guinea Worm cases and endemic villages has been decreasing steadily [4,8]. When The Carter Center began their Guinea Worm Eradication Program in 1986 there were approximately 3.5 million cases annually and 20 endemic countries, primarily in Africa and Asia [5, 6,8]. Ghana became the most recent country to have eliminated Guinea Worm, the WHO declared it Guinea Worm-free in May 2010 [7]. Since 2012, the disease has been limited to 4 countries in Africa - South Sudan, Mali, Chad, and Ethiopia [6]. In 2014 there were only 30 endemic villages and 126 cases, with 70 cases in South Sudan, 40 in Mali, 13 in Chad, and only 3 in Ethiopia [5]. This means Guinea Worm has been eliminated in Asia, is being controlled in Africa, and is rapidly moving towards the universal goal of eradication. If successful, Guinea Worm would become the first human infectious disease to be eradicated without the use of a vaccine or medication [8].

 

 

Sources:

[1] http://www.who.int/csr/disease/smallpox/en/

[2] http://www.oie.int/for-the-media/rinderpest/

[3] http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2305684/pdf/bullwho00391-0020.pdf

[4] http://www.who.int/dracunculiasis/disease/en/

[5] http://outbreaknewstoday.com/guinea-worm-disease-126-cases-reported-in-2014/

[6] http://www.who.int/dracunculiasis/epidemiology/en/

[7] http://www.who.int/dracunculiasis/eradication/en/

[8] http://www.cartercenter.org/health/guinea_worm/index.html

H5N1 Resurfaces in Nigeria

Feb 9, 2015 | Colleen Nguyen | Outbreak News

H5N1 has resurfaced in Africa’s most populous country, Nigeria. As of January 30, 2015, 11 out of 36 states across the nation have reported cases of avian influenza in poultry [1]. The outbreak seems to have begun in the northern states of Kano and Lagos. Kano State has been hardest hit thus far, with an estimated 136,905 infected birds and a 13% mortality rate [2]. However, the 13% mortality rate of infected birds in this outbreak may not be entirely accurate, due to the nature of large-scale poultry cullings in outbreaks of H5N1. Other affected states include: Ogun, Delta, Rivers, Plateau, Edo, Imo, Gombe, Jigawa, and Oyo [2]. This is not Nigeria’s first detection of this highly pathogenic strain of influenza. In fact, H5N1 was first detected in Nigerian poultry in 2006, and claimed the country’s first human death in 2007 [2].

 

What About H5N1?

According to the CDC, H5N1 -- a highly pathogenic subtype of the influenza virus -- “occurs mainly in birds, is highly contagious among birds, and can be deadly to them, especially domestic poultry” [3]. While rare, human cases have been reported worldwide, with some leading to death [3]. As of January 30th, Egypt’s Ministry of Health has reported at least 31 human cases and 10 deaths from H5N1 so far this year [1]. Generally, H5N1’s most common symptoms include fever and cough, with possible complications including respiratory failure and acute respiratory distress syndrome [3]. Research shows that those who work directly with poultry and birds are at higher risk of becoming infected. The mortality rate for H5N1 in humans hovers around approximately 60% [5].

 

What’s Nigeria Doing?

Lagos, the state with Nigeria’s largest commercial city and a population boasting 15 million, has provided prevention measures to the public to further prevent the spread of H5N1 [4]. Lagos State’s Commissioner for Health, Dr. Jide Idris, “advised members of the public to avoid contact with chickens, ducks or other birds, including their feathers, faeces and other wastes in areas where the disease is known to exist” [4]. Additionally, proper hand hygiene was emphasized to aid in halting the spread of H5N1 [4]. Dr. Idris also reiterated that sick and dead poultry be kept away from children and that all poultry should be cooked thoroughly [4]. In regards to surveillance, Dr. Idris “pleaded with the general public to be watchful and report any casualty with a history of having been in direct or indirect contact with dead poultry or confirmed case of the disease to the health and agricultural departments of the nearest Local Government Area office, or to the Directorate of Disease Control in the State Ministry of Health” [4].

 

Sources

[1] http://www.promedmail.org/direct.php?id=20150130.3132222

[2] http://www.reuters.com/article/2015/01/29/us-health-birdflu-nigeria-idUSKBN0L21AH20150129

[3] http://www.cdc.gov/flu/avianflu/h5n1-virus.htm

[4] http://www.channelstv.com/2015/02/02/lagos-state-gives-measures-to-prevent-bird-flu-spread/

[5] http://www.flu.gov/about_the_flu/h5n1/

 

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