Several news stories and epidemiological updates on the yellow fever outbreak in Brazil:
Brazil orders 11.5 million yellow fever vaccines amid worst outbreak in years
From Straitstimes.com: Rio de Janeiro said on Saturday (March 11) it plans to vaccinate the state’s entire population against yellow fever in response to an outbreak that has killed at least 113 people around Brazil. Although Rio has not registered any cases, it is close to where the disease has taken hold in the neighbouring states of Minas Gerais, Espirito Santo and Sao Paulo. The aim is “to expand the strategy of vaccination as a preventative measure”, the Rio health department said in a statement.
The state government said it’s aiming to vaccinate the whole population by the end of the year. A total of 12 million doses will be required, with three million already ordered, the statement said. Brazil’s health ministry says that yellow fever, which is carried by mosquitoes, has been confirmed in 352 cases, with another 915 under investigation in an unusually severe outbreak. So far 113 deaths have been confirmed from the disease, with 104 more under investigation.
New England Journal of Medicine essay:
Yellow Fever — Once Again on the Radar Screen in the Americas
Catharine I. Paules, M.D., and Anthony S. Fauci, M.D. March 8, 2017
World Health Organization and Pan American Health Organization report:
Epidemiological Update – Yellow Fever – 9 March 2017
The substantial increase in human cases of avian influenza A(H7N9) in China, to which BCCDC alerted you earlier this year, continues.
- During this fifth wave beginning in October 2016, the number of human A(H7N9) cases reported in China has surpassed the number of cases reported in any of the four prior waves since the virus was first identified in February 2013 (see Figure below).
- As of March 1, 2017, a cumulative total of 1,258 confirmed human A(H7N9) infections and at least 328 deaths have been reported to the World Health Organization (WHO). More than one-third of these cases (n=460) were reported since October 2016.
- As in prior waves, the majority of reported cases are older adult males, with at least one-third fatal. Most cases have reported recent exposure to infected poultry or contaminated environments, including live poultry markets. A few clusters have occurred for which limited human-to-human transmission cannot be ruled out.
- Avian influenza A(H7N9) has previously been considered a low-pathogenic avian influenza (LPAI) virus, meaning that it causes little or no disease in poultry. However, on February 18, 2017 the WHO was notified of two previously reported human A(H7N9) cases that had been infected with a highly pathogenic avian influenza (HPAI) virus. HPAI A(H7N9) viruses were also detected at live poultry markets in China from birds sampled in January 2017. Of note, LPAI and HPAI designations refer to severity in poultry but are not predictive of severity in humans.
- Genetic sequencing also revealed that these viruses had acquired mutations conferring resistance to neuraminidase inhibitors (NIs), although both patients had received oseltamivir treatment before specimens were collected. Sporadic detection of A(H7N9) viruses with mutations conferring reduced sensitivity to NIs has been reported previously but these have not become established/ongoing causes of human illness. To date, there has been no evidence of increased pathogenicity in humans or transmission between humans associated with these genetic changes, although continued monitoring is warranted.
Key action and advice:
- For travellers to affected areas: Maintain strict personal, hand, food and environmental hygiene and avoid touching birds, poultry or their droppings or visiting markets, farms or other areas potentially contaminated by poultry droppings. All poultry and poultry products that are consumed, including eggs, should be thoroughly cooked. In the event of illness within 2 weeks of return to Canada that requires medical care, actively inform clinicians of travel abroad so they can manage and investigate appropriately.
- For attending clinicians: Maintain vigilance and actively elicit relevant travel and exposure history from patients presenting with acute illness that could be due to infectious disease, notably severe acute respiratory illness (SARI). If there are links to affected areas in the two weeks prior to symptom onset, notify the local Medical Health Officer and consult a microbiologist at the BCCDC Public Health Laboratory for testing advice, clearly indicating any relevant travel/exposure history with specimen submission. Follow strict infection prevention and control guidelines when collecting respiratory specimens.
For more information:
May 10, 2017
Hyatt Regency Montreal
The Vaccine Innovation Conference will be held May 10, 2017 in Montreal hosted by the Vaccine Industry Committee. This one day conference will include academic, industry and government leaders focusing on vaccine innovation in Canada. The goal of this one-day event is improved knowledge exchange and awareness of Canadian vaccine innovations and accomplishments to support investment for vaccine R&D. The Vaccine Innovation Conference is being held in conjunction with the Canadian Society for Pharmaceutical Sciences (CSPS) annual conference, May 10-13, 2017.
What is the conference offering?
This one-day conference is a snapshot of the best of Canada’s vaccine research and local and international organizations, companies or biotechs should consider attending the conference to discover this fruitful Northern scientific ecosystem.
The preliminary program for the 2017 conference is now available online at vaccineinnovationconference.ca.
Session topics include:
- emerging disease vaccines
- cancer vaccines
- global health vaccines: parasites and TB
- vaccine technologies
There will also be a panel discussion on funding of vaccine research and development in Canada.
You can register here.
A team led by Danuta Skowronski (Epidemiology Lead, Influenza & Emerging Respiratory Pathogens) of the BC Centre for Disease Control, published a scientific paper last week in the Journal of Infectious Diseases (JID) that may also be of interest to you. The paper reflects the collaborative input of investigators from the Canadian Sentinel Practitioner Surveillance Network (SPSN) and the University of Cambridge (UK).
In this paper, the effects of annual repeat influenza vaccination are addressed, including several key perspectives:
- Historical observations, dating more than 40 years ago, including findings during UK boarding school A(H3N2) outbreaks in the 1970s, and a US randomized controlled trial in the 1980s, illustrated in the Supplementary Material.
- Major explanatory hypothesis – called “the antigenic distance hypothesis” – articulated during the 1990s by Smith et al to reconcile variability in annual repeat influenza vaccination effects based on the relatedness (or antigenic distance) between prior (v1) and current (v2) season’s vaccines, and the current season’s epidemic (e) strain.
- Epidemiological findings during three recent A(H3N2) epidemics in Canada (2010, 2012, 2014), interpreted within the framework of the antigenic distance hypothesis.
- Immunological theories beyond (or complementary to) the antigenic distance hypothesis to explain the potential negative effects of annually repeated influenza vaccination.
This is the first modern attempt to directly correlate antigenic distance metrics with epidemiological observations of repeat influenza vaccination effects based on the test-negative design. The authors show good overall consistency between epidemiological findings and predictions of the antigenic distance hypothesis.
The article has been selected as “Editor’s Choice” by JID and an invited commentary by Dr. John Treanor of the University of Rochester accompanies its publication. Both are freely available in Advance Open Access format at the links below:
Accompanying commentary (J Treanor): https://academic.oup.com/jid/article/2979769/Flu-vaccine-too-much-of-a-good-thing
The Center for Infectious Disease Research and Policy (CIDRAP) has reported on the article, available here: http://www.cidrap.umn.edu/news-perspective/2017/02/studies-shed-light-effects-serial-flu-shots-current-vaccines-benefits