World running out of effective antibiotics!

World Heath Organization – A September 2017 report released by WHO shows a serious lack of new antibiotics under development to combat the growing threat of antimicrobial resistance. It seems that most of the drugs currently in the clinical pipeline are modifications of existing classes of antibiotics and are only short-term solutions. The report found very few potential treatment options for those antibiotic-resistant infections identified by WHO as posing the greatest threat to health, including drug-resistant tuberculosis which kills around 250,000 people each year.

"Antimicrobial resistance is a global health emergency that will seriously jeopardize progress in modern medicine," says Dr Tedros Adhanom Ghebreyesus, Director-General of WHO. "There is an urgent need for more investment in research and development for antibiotic-resistant infections including TB, otherwise we will be forced back to a time when people feared common infections and risked their lives from minor surgery."

The report went on to conclude that there is a serious lack of treatment options for multi-drug and extensively drug-resistant M. tuberculosis and gram-negative pathogens, including Acinetobacter and Enterobacteriaceae (such as Klebsiella and E.coli) which can cause severe and often deadly infections that pose a particular threat in hospitals and nursing homes....

See Antibacterial agents in clinical development.

WHO recommends changes to flu vaccine!

The World Health Organization (WHO) yesterday (Sept 25, 2014) recommended changing two of the three strains in trivalent influenza vaccines for use next year in the Southern Hemisphere, because of signs that changes in circulating strains have made them less well matched to the current vaccine.
The WHO called for switching the A/H3N2 and B strains in trivalent vaccines. For quadrivalent (four-strain) vaccines, which contain two B strains, the agency recommended no change in the second B component. The A/H1N1 strain in the vaccine also should stay the same, the WHO said.
"Increasing proportions of the recently circulating A(H3N2) and influenza B Yamagata-lineage viruses have undergone antigenic drift since the last vaccine recommendation," the agency said in a question-and-answer statement accompanying the vaccine recommendation.

Because of the time it takes to prepare vaccine viruses and grow them in eggs or mammalian cell cultures, the WHO recommends the vaccine strains in September for the following year's Southern Hemisphere flu season and in February for the Northern Hemisphere season.
The WHO recommends the following for trivalent vaccines:

• For H1N1, an A/California/7/2009-like virus
• For H3N2, an A/Switzerland/9715293/2013 virus
• For type B, a B/Phuket/3073/2013-like virus (belonging to the Yamagata lineage)
  

For quadrivalent vaccines, the agency recommended using the same strain as in the current Northern Hemisphere vaccine for the second B strain: B/Brisbane/60/2008, which belongs to the Victoria lineage.

Quadrivalent vaccines have been developed in recent years because of the difficulty of predicting which B lineage, Victoria or Yamagata, will dominate in any season. Yamagata viruses have remained dominant over Victoria strains over the past 8 months, the WHO said.

Antigenic drift

To assess the match between flu vaccines and circulating flu viruses, WHO laboratories take serum from vaccinated ferrets and humans and examine how well the antibodies in the serum react with circulating viruses.
Most recently isolated H3N2 viruses were antigenically distinguishable from the H3N2 virus in the current Northern Hemisphere vaccine, called A/Texas/50/2012, and more closely matched A/Switzerland/9715293/2013, the WHO said.

"Current vaccines containing A/Texas/50/2012 antigens induced antibodies in humans that reacted less well to A(H3N2) clade 3C.3a viruses," the agency said.
The strains in the current Northern Hemisphere vaccine are the same as in last year's version and in the 2014 Southern Hemisphere vaccine.

Low drug resistance

In a note on drug resistance, the WHO report said the "vast majority" of H3N2 and B isolates analyzed in recent months were susceptible to available antivirals, including oseltamivir (Tamiflu), zanamivir (Relenza), peramivir (sold in Japan as Rapiacta), and laninamivir (sold in Japan as Inavir).
It said most H1N1 viruses also were susceptible to the drugs, but a small proportion of tested H1N1 isolates showed resistance. In Japan, 2.7% of isolates showed resistance to oseltamivir and peramivir.