News Scan for Jan 02, 2020

News brief

WHO: 8.5 million malaria cases in Burundi

A massive malaria outbreak in Burundi continues, according to the latest update from the World Health Organization's (WHO) African regional office. Since the last update at the end of October, an additional 1.3 million cases and 479 deaths have been recorded, bringing the outbreak total to more than 8.5 million cases.

Between Jan 1 and Dec 15 of 2019, a total of 3,170 fatalities have been reported. Although cases have been reported across the country, the highest infection rates come from 19 districts located in the eastern part of the country, the WHO said.

"Interruption of the transmission requires scale-up of high-impact and targeted interventions, including distribution of insecticide-treated bed nets and indoor residual spraying, along with risk communication interventions and set up of mobile clinics in all affected areas," the WHO said.

The rates of malaria are at a 5-year high for Burundi, and disease activity in 2019 was up 64.6% compared with 2018.
Dec 29 WHO update

 

Study shows IV delivery improves efficacy of TB vaccine in monkeys

A study conducted in monkeys suggests intravenous (IV) delivery of the tuberculosis (TB) vaccine could provide better protection against the disease than injecting it into the skin, researchers reported yesterday in Nature.

The study, which was led by scientists from the National Institute of Allergy and Infectious Diseases (NIAID) and the University of Pittsburgh School of Medicine, compared IV delivery of the BCG (Bacille Calmette-Guérin) vaccine—an attenuated strain of Mycobacterium bovis—in rhesus macaques with four other modes of delivery: the conventional intradermal (ID) route, the ID route with a higher-than-normal dose, via aerosol, and through a combination of aerosol and the high-dose ID route. They monitored the immune response in the macaques over a period of 6 months, then exposed them to Mycobacterium tuberculosis, the bacteria that causes tuberculosis.

While ID and aerosol vaccination provided modest protection against pulmonary TB, nine out of 10 macaques that received IV vaccination were highly protected, with six having no detectable trace of M tuberculosis bacteria in their lungs and three having very low counts of bacteria. Analysis of the immune response revealed that, compared with ID or aerosol delivery, IV delivery induced substantially more antigen-responsive CD4 and CD8 T cell responses in blood, spleen, bronchoalveolar lavage, and lung lymph nodes, along with a high frequency of antigen-responsive T cells across all lung parenchymal tissues.

While the BCG vaccine has been administered to more than 1 billion children via the ID route since it was developed more than a century ago, its effectiveness in preventing pulmonary TB in adolescents and adults has varied. The authors of the study suggest that IV delivery may provide enhanced protection by getting the vaccine to the lungs, lymph nodes, and spleen more quickly and inducing a strong and durable T-cell response.

"In conclusion, this study provides a paradigm shift towards developing vaccines focused on preventing TB infection to prevent latency, active disease and transmission," they write. "This study also provides a benchmark against which future vaccines will be tested and a new framework to understand the immune correlates and mechanisms of protections against TB."

The researchers say they eventually hope to test an IV BCG vaccine in humans.
Jan 1 Nature study
Jan 1 University of Pittsburgh press release

 

H5N8 avian flu strikes Polish turkey farm

Animal health officials in Poland have reported a highly pathogenic H5N8 avian influenza at a turkey farm in Lubelske region, located in the southeastern part of the country, according to a notification today from the World Organization for Animal Health (OIE).

The event began on Dec 30, and testing in the wake of suspected avian influenza found the virus is samples taken from five dead birds. As part of the outbreak response, the flock of 12,089 birds were culled.

Poland's last H5N8 outbreak occurred in April 2017.
Jan 2 OIE report

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