News Scan for Aug 17, 2015

News brief

WHO: Sierra Leone down to single Ebola transmission chain

Sierra Leone is down to its last known Ebola transmission chain, a sign of continuing progress in the battle against the disease, the World Health Organization (WHO) announced today. It added that the country has now gone a full epidemiologic week without a new case for the first time since the outbreak began last year.

The WHO said Sierra Leone's use of rapid response teams and strong community involvement to pinpoint cases and contacts have been yielding results. Anders Nordstrom, MD, the WHO's representative in Sierra Leone, said in a statement today that the achievements are encouraging, "but we have to keep doing this intensive working with the communities to identify potential new cases early and to rapidly stop Ebola transmission."

Sierra Leone's last known transmission chain started in Freetown and triggered a cluster of cases in Tonkolili district in the northern part of the country. The index patient in the chain was a young man who worked in Freetown but returned to his home village each month to bring his family food and money.

The man died in a hospital where he was being treated for a suspected malaria infection. Based on established protocols, a swab was taken and tested positive for Ebola virus.

The man's village was quarantined for 21 days, and two more people—both from the man's family—got sick with Ebola. On Aug 14, 595 people from Tonkolili were released from quarantine, some of them healthcare workers. The WHO added that 43 people are still in quarantine until the end of this week, with 38 more people in Freetown in quarantine until Aug 29.
Aug 17 WHO statement

CDC: Salmonella in Washington state pork outbreak is multidrug resistant

The 134-case Salmonella outbreak in Washington state that has been linked to pork involves a multidrug-resistant form of the bacterium, the Centers for Disease Control and Prevention (CDC) reported late last week.

In an Aug 14 outbreak update, the CDC said that all three patients' Salmonella samples tested were resistance to ampicillin, streptomycin, sulfisoxazole, and tetracycline. The outbreak strain is Salmonella I 4,[5],12:i:-. In a recent annual report on antibiotic-resistance in foodborne bacteria, the Food and Drug Administration said multidrug resistance in the subtype has doubled over the past few years.

The CDC also noted that 16 people have been hospitalized in the outbreak. No deaths have been reported. Illness-onset dates range from Apr 25 to Aug 1, and patients' ages vary from 1 to 90 years, with a median of 35.

Kapowsin Meats in Graham, Wash., on Aug 13 recalled more than 116,000 pounds of whole pigs after the outbreak strain was detected in samples collected at its plant.
Aug 14 CDC update
Aug 13 CIDRAP News story "Report on drug-resistant foodborne bacteria reveals encouraging trends, a few red flags"

Polio Scan for Aug 17, 2015

News brief

Study finds injected polio vaccine safe

Thirteen years of US safety data on the inactivated poliovirus vaccine (IPV, or polio shot) show that it is not associated with major side effects, a study yesterday in The Lancet Infectious Diseases noted.

Researchers from the Centers for Disease Control and Prevention, the Food and Drug Administration, and Emory University in Atlanta studied data on 41,792 adverse events submitted to the US Vaccine Adverse Event Reporting System (VAERS) from Jan 1, 2000, through Dec 31, 2012.

Given that more than 250 million IPV doses were administered during that period, the rate of adverse events was about 0.02%. Also, stand-alone IPV administration was recorded for only 0.5% of the events, as most doses were given in combination with other childhood vaccines.

Among the adverse events reported, 34,880 (88%) were for non-serious events, 3,905 (10%) were for non-fatal serious events (10%), and 783 (2%) were death reports. Almost all deaths (96%) were in children 1 year old or younger, and 52% had sudden infant death syndrome as the reported cause of death. These rates are similar as data on the oral polio vaccine, the authors noted.

The researchers concluded, "No new or unexpected vaccine safety problems were identified." An accompanying commentary called the results "good news."
Aug 16 Lancet Infect Dis study
Aug 16 Lancet Infect Dis commentary

WHO panel calls on Pakistan, Afghanistan to ramp up polio efforts

The World Health Organization's (WHO's) emergency committee on polio today said that the disease continues to constitute a Public Health Emergency of International Concern (PHEIC) and called for stepped-up elimination efforts in Pakistan and Afghanistan as it recognized recent progress there.

The committee noted that Pakistan has reported less than a third of the cases so far this year compared with 2014, no exported cases since October 2014, and fewer children missed by vaccination teams.

"Despite this improvement, however, Pakistan has had 85% of all global wild polio virus cases in 2015," the WHO noted in a statement. "The risk of new exportations from Pakistan remains, with ongoing transmission in the country during the low transmission season, and the commencement of the high transmission season in May."

The panel added that Pakistan and Afghanistan have historically shared a "vast common zone of poliovirus transmission," but added that the recent spread between the two countries is from "discrete zones of persistent transmission" in each country.

The agency noted that countries especially vulnerable to polio importation include war-torn nations in the Middle East, the Horn of Africa and central Africa, particularly the Lake Chad region.
Aug 17 WHO statement