The Top 5 articles this past week honed in on the mosquito-borne viruses yellow fever and Zika virus, in addition to meningococcal disease and human papillomavirus (HPV). The first article brings attention to the potential for yellow fever to become a transcontinental threat, while our second article focuses on why a specific meningococcal vaccine was administered during an outbreak at Rutgers University in 2016. The third most-read article of the week includes information on a team of researchers, including Contagion®
’s own Editorial Advisory Board member, Adriano de Bernardi Schneider, MS, who used computational modeling tools to phylogenetically map the evolution of the Zika virus, and shed some light on why it is causing birth defects and Guillain-Barré syndrome in adults. In addition, our second most-read article of the week highlights research from the Centers for Disease Control and Prevention which revealed new information that will help to determine whether cases of Zika virus are locally-acquired or travel-related. This will help with prevention efforts in the United States. Finally, our top article of the week covered research from the 2017 CDC EIS Conference which showed the first statistical evidence that the HPV vaccine is providing herd immunity against infection in the target population.
#5: Yellow Fever: A Transcontinental Threat?
Concerns continue to mount in the healthcare community over outbreaks of yellow fever that are plaguing Africa and the Americas. In fact, yellow fever is the most severe of the five emerging and reemerging arthropod-borne viruses that are spreading rapidly throughout the Americas, particularly in populations that have not previously been exposed to them (such as urban centers where the vaccine for the virus is not regularly administered).
The virus has infected hundreds of individuals in Brazil, and is to blame for more than 200 deaths. Although public health officials are not concerned about an outbreak in the continental United States, Puerto Rico remains vulnerable to the virus and, “travel-related cases of yellow fever could occur, with brief periods of local transmission in warmer regions such as the Gulf Coast states, where Aedes aegypti
mosquitoes are prevalent.”
To prevent future outbreaks in Brazil and other areas around the world, healthcare officials are calling for rapid and early identification of cases as well as “implementation of public health management and prevention strategies, such as mosquito control and appropriate vaccination.”
In related news, the World Health Organization and Institut Pasteur are calling attention to a case of an alarming case of yellow fever and Japanese encephalitis virus coinfection discovered in a 19-year-old male from Angola with no history of travel. Researchers from both organizations warned that “increased levels of population movement between Asia and Africa may provide opportunities for pathogens to expand their geographic range.” Although this is only one case of coinfection, “Angola has suitable vectors and hosts for Japanese encephalitis, [and so] increased serosurveillance is advisable.”
Read more about the transcontinental threat of yellow fever here
#4: Why Was a Specific Meningococcal Disease Vaccine Recommended for the 2016 Rutgers Outbreak?
Whole-genome sequencing enabled individuals at Rutgers University to receive personalized vaccines against meningococcal infections discovered in two undergraduate students in the spring of 2016. A specific meningococcal vaccine called Trumenba was recommended and administered to around 35,000 individuals throughout the university.
The two vaccines that are currently available to treat meningitis in the United States are a 2-dose series of Bexsero (MebB-4C) or a 2- or 3-dose series of Trumenba (MenB-FHbp). Either drug can be used for outbreak response; however, because each vaccine targets different antigens, they are not interchangeable. “The same brand must be used for all doses” when vaccinating an individual.
Because whole-genome sequencing of the samples taken from the two infected students revealed that the antigens in their samples were a mismatch for the antigen targeted by Bexsero, healthcare officials were concerned that vaccine would not provide viable protection. “Although the outbreak strain antigens also did not exactly match those included in Trumenba, cross-protection with Trumenba was expected based on prior testing by the manufacturer,” and therefore, healthcare officials chose that vaccine as the more viable option. Further testing revealed that a 3-dose course of the vaccine would offer the best protection against the outbreak strain.
Learn more about this rare exception to the general recommendation for meningococcal vaccination here