A medical situational heads up!

A particularly dangerous super bug, dubbed the "phantom menace" by scientists, is on the rise in the United States, according to a report Thursday by the Centers for Disease Control and Prevention.

This super bug's strains belong to the family of bacteria known as CRE (Carbapenium Resistant Enteriobacterace), which are difficult to treat because they are often resistant to most antibiotics and can spread this resistance to other bacteria via little packets of genes known as plasmids. They are often deadly, too, in some instances killing up to 50 percent of patients who become infected, according to the CDC. Health officials have called CRE among the country's most urgent public health threats.

In a recent ProMed report out of India, most infections occurred when a patient got transferred to a rehab after suffering a medical problem. They then contract CRE from a careless healthcare worker who fails to wash their hands properly and thus transmit the bacteria. The patient then gets worst and is sent back to the hospital when another 'hand off' occurs and so the process continues. As, you might gather form this, most of those affected are elderly. But, this may not be the case for long. [A personal opinion - A copy of the ProMed report is available here]

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.