News Scan for Jan 09, 2015

News brief

WHO approves meningococcal vaccine for African infants

The World Health Organization (WHO) today approved a meningococcal vaccine for infants in sub-Saharan Africa that has already proved successful in older children and young adults along the continent's "meningitis belt," the agency said in a news release.

The WHO approved a 5-microgram dose of MenAfriVac, made by the Serum Institute of India Ltd, through its prequalification process for children younger than 1 year. The vaccine, billed as affordable, has already dramatically reduced outbreaks of meningococcal group A in the meningitis belt, which stretches from Senegal in the west to Ethiopia. It was introduced in 15 nations in that corridor in 2010 for people 1 to 29 years old.

Results from two clinical studies in infants in Ghana and Mali and vaccine introduction "impact data" were presented to the WHO Strategic Advisory Group of Experts (SAGE) on Immunization in October 2014, and the SAGE panel concluded that a one-dose schedule at 9 months of age or older was recommended to achieve continued success following the initial mass campaigns in the older age-group.

The WHO prequalification allows United Nations procurement agencies to buy the vaccine for use in meningitis-belt countries, the WHO said in the release. Seven countries—Burkina Faso, Cameroon, Chad, Ghana, Mali, Niger, and Nigeria—are slated to introduce MenAfriVac as early as this year, while mass vaccination campaigns continue in the other countries.

"We are more than halfway through with introducing the vaccine in meningitis-belt countries, and the first introductions have been a stunning success," said Jean-Marie Okwo-Bele, MD, director of the WHO Department of Immunization, Vaccines and Biologicals. "But we cannot yet declare a win on meningitis epidemics in sub-Saharan Africa."
Jan 9 WHO news release


Dengue vaccine effectiveness trial in Latin America called milestone

An investigational recombinant tetravalent dengue vaccine, CYD-TDV from Sanofi Pasteur, was shown in a phase 3 trial in five Latin American countries to have more than 60% efficacy overall as well as to substantially decrease the rate of severe cases and hospitalizations for dengue. The study was published yesterday in the New England Journal of Medicine.

The study population included 20,869 healthy children aged 9 to 16 years from 22 centers in five countries in which dengue is endemic—Colombia, Brazil, Mexico, Puerto Rico, and Honduras. Subjects were assigned in a 2:1 ratio to receive three doses of either vaccine or placebo at 0, 6, and 12 months; they returned at month 13 and were contacted by phone or home visits at 18 and 25 months for follow-up, including testing for dengue serotype–specific antibodies.

Subjects and their parents were reminded during weekly contacts to be seen if an acute febrile illness occurred; blood, lab, and imaging results were recorded for children having such illnesses.

Overall vaccine efficacy was found to be 64.7% (95% confidence interval [CI], 58.7% to 69.8%) in subjects who received at least one dose of vaccine and 60.8% (95% CI, 52.0% to 68.0%) in those receiving all three doses.

Vaccine efficacy was highest against serotype 4 dengue and lowest against type 2. In children who had antibodies against dengue at baseline, efficacy was 83.7% (95% CI, 62.2% to 93.7%), compared with 43.2% (95% CI, –61.5% to 80.0%) in those who did not.

Among children receiving at least one dose of vaccine, there were 17 hospitalizations for lab-confirmed dengue, compared with 43 for controls, for an efficacy rate against hospitalization of 80.3% (95% CI, 64.7% to 89.5%). Severe cases of infection occurred in 1 child in the vaccine group and 11 in the control group, for an efficacy rate against severe disease of 95.5% (95% CI, 68.8% to 99.9%) after the first injection.

An accompanying commentary in the same issue called the study's results "a milestone" and said, "Practitioners should remain optimistic that one day it will be possible to prevent dengue."
Jan 8 N Engl J Med article
Jan 8
N Engl J Med commentary


Saudi Arabia reports 2 new MERS cases

Saudi Arabia's Ministry of Health (MOH) today reported two new MERS-CoV cases, in Riyadh and Taif, bringing the year's total to eight.

The case in Riyadh involves an 80-year-old man who had no recent animal exposure or exposure to other patients with MERS-CoV (Middle East respiratory syndrome coronavirus). He is not a healthcare worker (HCW). The MOH has reported a case in Riyadh on each of 4 consecutive days.

The patient in Taif is a 31-year-old male expatriate who is also not an HCW. He had no contact with MERS patients but did have indirect exposure to animals. The MOH did not specify the nature of the exposure.

Both men have preexisting disease and are hospitalized in stable condition.

The infections raise Saudi Arabia's MERS-CoV count to 833 cases, including 358 fatalities; 9 patients are currently being treated for the disease.
Jan 9 MOH update


Taiwan reports H5N2 outbreak in chickens

Taiwanese officials confirmed an outbreak in chickens of highly pathogenic H5N2 avian flu on a farm in Pingtung County's Xinpi Township, according to a report today from the Taiwan Central News Agency (CNA).

The Pingtung Agriculture Department is culling all 120,000 chickens at the affected farm, identified as Dawushan Livestock Products Co. The department is disinfecting the farm and banning all transport of chickens in the region.

Confirmation of H5N2 in Dawushan chickens came today, following the report of chicken deaths on the farm last month and continuing deaths despite vaccination efforts, the CNA said.

This is the first outbreak of H5N2 reported at the farm. Poultry farms in the area have not reported avian flu outbreaks, although there are reports of geese and ducks dying suddenly in nearby Xinyuan and Wandan townships.

Dawushan is one of the leading chicken farms in Taiwan, and eggs from the farm have been shipped and may still be available to consumers. The Agriculture Department continues to monitor poultry farms in the county for avian flu outbreaks, the story said.

No associated human H5N2 infections have been reported.
Jan 9 Taiwan CNA report


California-based company recalls apples in wake of Listeria outbreak

Bidart Bros. apple packing facility has voluntarily recalled all Granny Smith and Gala apples after environmental sampling detected listeria contamination at the plant, according to a Centers for Disease Control and Prevention (CDC) update yesterday.

The recall issued on Jan 6 follows the implication of apples packaged by Bidart Bros. in an 11-state Listeria outbreak that has sickened 32 people. All but 1 person have required hospitalization, and 6 people have died. All listeriosis cases were related to consumption of commercially produced, pre-packaged caramel apples.

On Jan 5, the US Food and Drug Administration (FDA) confirmed Listeria contamination at the Bidart Bros. plant, which is based in Shafter, Calif. The Jan 6 recall affects all Granny Smith and Gala apples packed by Bidart Bros., and consumers are advised not to eat these apples and to question retailers about apples' sources.

The recent apple recall follows the company's December 2014 recalls of Granny Smith apples used to make pre-packaged caramel apples sold by Happy Apples, California Snack Foods, and Merb's Candies.

The FDA is running further tests to determine whether the Listeria samples detected at the Bidart Bros.' apple packaging facility match outbreak samples. The FDA and CDC are also working with Canadian health authorities to determine whether two Canadian Listeria cases are related to caramel apples imported from the United States.
Jan 8 CDC update
Jan 8 FDA update
Dec 31 CIDRAP News scan on Listeria

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