WHO updates Zika vaccine target profile, announces research grants
A World Health Organization (WHO) working group recently updated its Zika vaccine target profile, a document used to inform vaccine developers, regulators, and other stakeholders. The group published the first version of the profile in July 2016, and the revision takes into account new data from the past 6 months.
The WHO has spelled out two scenarios for use of a vaccine: outbreak response involving mass vaccination campaigns targeting reproductive-age women and routine use in endemic areas that would target the general population.
The 17-page document spells out the preferred and minimal characteristics for a vaccine for emergency use and covers indications (for people 9 years old and older) and contraindications (none in pregnant or lactating women). The preferred vaccine would be a nonreplicating one with no safety concerns for use during pregnancy, with the minimal characteristic a single-replicating vector platform with robust safety data or a live, attenuated platform with acceptable safety data. The profile also prioritizes a single-dose vaccine that protects for more than 1 year, can be co-administered with other vaccines, and has a shelf life of at least 12 months.
In other Zika developments:
- The Pan American Health Organization (PAHO) and the WHO yesterday announced a joint initiative to support 17 new Zika research in Latin America and the Caribbean, according to a statement from PAHO, which is the WHO regional office. The projects range from identifying transmission risk factors to examining prenatal counseling. The research projects are based at academic institutions and nongovernmental organizations in Brazil (7), Colombia (4), and Peru (2), with 1 each in Honduras, Jamaica, Mexico, and Venezuela. Each group will receive up to $20,000 from the WHO small grants program.
- The US Centers for Disease Control and Prevention (CDC) recently released two Zika-related toolkits for health providers, one aimed at obstetricians and the other meant for pediatricians. The publication for obstetricians covers diagnosis, testing, and reporting, and the guide for pediatricians addresses identification of congenital Zika infections, along with diagnosis and reporting.
PAHO: Downward yellow fever trend in Brazil outbreak area
Yesterday the Pan American Health Organization (PAHO) posted a yellow fever update, and noted again a downward trend in cases reported at the epicenter of Brazil's outbreak, Minas Gerais state.
Since PAHO's last update on Feb 16, there have been 100 new suspected human cases and 18 more deaths, raising the total of suspected cases to 1,336 and lifting the total number of deaths to 215. The case-fatality rate is 35% among confirmed cases and 12% among suspected cases.
Since last week, three more states have reported suspected or confirmed cases of the mosquito-borne disease, including Bahia (9), Espirito Santo (177), Minas Gerais (1,008), Rio Grande do Norte (1), Sao Paulo (10), and Tocantins (2). So far the states reporting confirmed cases remain at three: Espirito Santo, Minas Gerais, and Sao Paulo.
So far there have been no cases in neighboring countries, but this week brought news of increased cases in non-human primates. According to PAHO, a total of 236 new epizootics were reported and are under investigation. There is still no evidence that the Aedes aegypti mosquito is playing a role in transmission.
Feb 23 PAHO update
Canada approves final rule allowing irradiated ground beef
Canada's government this week finalized rules that allow meat producers to sell fresh and frozen ground beef treated with irradiation.
Health Canada said in a Feb 22 statement that it developed the new regulations after a thorough assessment, concluding that it is a safe and effective method for reducing harmful bacteria in ground beef. It added that irradiation is an optional tool that the food industry can use to maintain quality or enhance safety. Rules require the Radura symbol to appear on packages of irradiated beef, or that it appear at the point of sale for unpackaged ground beef.
The United States allowed irradiation for fresh and frozen ground beef in 1999, and more than 60 countries allow irradiation in various foods. Canada already allows it to treat potatoes, onions, wheat, flour, spices, and seasoning mixes.
Food Safety News (FSN) reported today that Canadian meat producers requested the rule change in 1998 and that Health Canada last considered irradiation for ground beef in 2002. Producers recently asked it to reconsider.
Feb 22 Health Canada press release
Feb 24 FSN story
Candidate E coli vaccine proven safe, immunogenic in phase 1 trial
A phase 1 trial of an experimental four-strain Escherichia coli vaccine found it was safe and produced a strong immune response against all vaccine serotypes for urinary tract infections (UTIs) in women, according to data released yesterday in The Lancet Infectious Diseases.
In the multicenter trial, researchers immunized 93 women with theExPEC4V candidate vaccine (produced by GlycoVaxyn and Janssen Vaccines) and 95 with a placebo. None of the women—all of whom had a history of UTIs—reported a serious side effect, and 56 (60%) vaccinated and 47 (49%) placebo women experienced at least one adverse event that was possibly, probably, or certainly related to the injection.
The team reported that vaccination induced significant Immunoglobulin G responses for all four vaccine serotypes 30 days after immunization. The researchers also reported significantly fewer UTIs caused by E coli of any serotype in the vaccine group compared with the placebo group, even though the phase 1 trial was not designed to measure vaccine effectiveness.
The authors conclude, "This tetravalent E coli bioconjugate vaccine candidate was well tolerated and elicited functional antibody responses against all vaccine serotypes. Phase 2 studies have been initiated to confirm these findings."
An accompanying commentary stated, "The preliminary results for this vaccine seem promising, and this trial is the first proof of concept in human beings that a vaccine might be effective against E coli infections. Further studies of different doses and formulations of the candidate vaccine, and of the vaccine's efficacy against invasive infections, are recommended."
Feb 23 Lancet Infect Dis study
Feb 22 Lancet Infect Dis commentary