News Scan for Feb 22, 2018

News brief

FDA oversees voluntary destruction, recall of kratom products

Days after the Centers for Disease Control and Prevention (CDC) said kratom, a plant used as an opioid substitute, was behind a multistate outbreak of Salmonella illness, the US Food and Drug Administration (FDA) announced that Botany Bay, Enhance Your Life, and Divinity by Divinity Products Distribution of Grain Valley, Mo., agreed to stop selling all products containing kratom, and voluntarily destroyed a high volume of kratom supplements.

"The extensive scientific data we've evaluated about kratom provides conclusive evidence that compounds contained in kratom are opioids and are expected to have similar addictive effects as well as risks of abuse, overdose and, in some cases, death. At the same time, there's no evidence to indicate that kratom is safe or effective for any medical use," said FDA Commissioner Scott Gottlieb, MD, in a statement yesterday.

Besides being labeled as an unregulated opioid, the FDA also said the recent Salmonella outbreak, which has not yet been linked to a specific brand of kratom, underscores the risk in taking any supplement that isn't subject to the FDA's control and safety protocols.

Kratom, a plant native to Southeast Asia, can be taken as a pill, powder, or tea, and is used as both a stimulant and a natural alternative to prescription opioids. The FDA said 44 deaths have been linked to kratom supplements.

On Feb 20, the CDC said 28 people in 20 states have fallen ill after consuming kratom. An outbreak investigation is ongoing.
Feb 21 FDA statement 
Feb 20 CIDRAP News scan on outbreak


Study says 1.8 million young people globally get TB each year

Almost 2 million people each year aged 10 to 24 years are infected with tuberculosis (TB) worldwide, with young adults at greatest risk, Australian researchers reported yesterday in the European Respiratory Journal.

Using the World Health Organization (WHO) database of TB notifications for 2012, the investigators estimated that 1.78 million (uncertainty interval [UI], 1.23 million to 3.00 million) young people developed TB that year, accounting for 17% of all cases globally. Southeast Asia (721,000 cases; UI, 473,000-1.35 million) and Africa (534,000; UI, 359,000-912,000) were hardest-hit for that age-group.

A commentary in the same issue points out that underdiagnosis is probably higher in children than it is in adults, so actual cases are likely higher.

Lead author Kathryn Snow, PhD, said in a European Lung Foundation news release, "The disruption caused by TB can have serious long-term impacts, but the scale of TB burden among this group has been generally unrecognized." She added, "Our next step is to try to understand the potential for targeting preventative measures specifically at young people in countries with intense TB epidemics."
Feb 21 Eur Respir J abstract
Feb 21 Eur Respir J commentary
Feb 21 European Lung Foundation news release


Study shows good protection for new oral rotavirus vaccine in children

In a study conducted in Indonesia, scientists have demonstrated that the experimental oral rotavirus vaccine RV3-BB protects well when the first dose is administered to newborns and when it is started at 8 weeks, according to a study today in the New England Journal of Medicine.

In the phase 2b study, the researchers administered the RV3-BB vaccine or a placebo according to a neonatal schedule (0 to 5 days, 8 weeks, and 14 weeks of age) or an infant schedule (8 weeks, 14 weeks, and 18 weeks of age). The study included 1,513 infants. A phase 2a study last year in New Zealand babies showed good immune response and a sound safety profile for the vaccine.

The new study involved a per-protocol arm and an intention-to-treat arm. According to the per-protocol findings, vaccine efficacy (VE) was 75% in the neonatal-schedule group, 51% in the infant-schedule group, and 63% in both groups combined. In the intention-to-treat analysis, VE was 68% in the neonatal-schedule group, 52% in the infant-schedule group, and 60% in the two groups combined.

The incidence of side effects was similar across the groups. No episodes of intussusception (a telescoping of the intestine) occurred within the 21-day risk period after administration of any dose of vaccine or placebo, and one episode of the complication occurred 114 days after the third dose of vaccine in the infant-schedule group.

The study was funded by the Bill and Melinda Gates Foundation and other funders. In September 2016, Batavia Biosciences, the maker of RV3-BB, announced an $8 million Gates Foundation grant to develop the vaccine.
Feb 22 N Engl J Med study
Sep 21, 2016, Batavia Biosciences news release


Avian flu outbreaks reported in Cambodia, South Africa, France

In the latest avian flu outbreak developments, Cambodia reported another highly pathogenic H5N1 event, South Africa confirmed another H5N8 detection in backyard poultry, and France reported poultry farm outbreaks involving two low-pathogenic strains, H5N2 and H5N3, according to separate reports from the World Organization for Animal Health (OIE).

In Cambodia, H5N1 struck backyard birds at a location in Prey Veng province in the southeastern part of the country. On Feb 11 the poultry owner reported high numbers of deaths and illnesses to provincial veterinary officials, and lab tests confirmed the findings on Feb 13. The virus killed 184 of 530 susceptible birds, and the survivors were culled to curb the spread of the disease. Cambodia has been reporting sporadic H5N1 outbreaks since December 2017.

South Africa reported an H5N8 outbreak in backyard poultry that began on Jan 29, killing 4 of 14 birds. The remaining ones were slated for culling. The country was hit hard by H5N8 outbreaks during the last half of 2017, but the pace of new detections has slowed considerably.
Feb 20 OIE report on H5N1 in Cambodia
Feb 22 OIE report on H5N8 in South Africa

In France, low-pathogenic avian flu detections continue to be reported on poultry farms, mainly from routine surveillance activities. The latest events include the Feb 19 H5N2 detection at a breeding duck farm in Nord department in the north of the country and three H5N3 detections on farms raising foie gras ducks, two in Gers department and one in Vendee department.

All the outbreaks began on Feb 15, and the ducks didn't show any clinical signs. As part of the outbreak response, authorities culled all 18,400 susceptible birds at the three foie gras locations.
Feb 21 OIE report on low-path H5N2 in France
Feb 21 OIE report on low-path H5N3 in France


Study profiles flu seasons for 118 countries

A study of flu surveillance data from 118 countries from 2011 to 2016 designed to identify seasonality patterns found that most countries in temperate climates have robust systems in place to track the disease, but large data gaps remain in equatorial countries, especially in parts of Africa. A research team based in Seattle published its findings yesterday in PLoS One.

The experts' country estimates of seasonal flu activity, based on WHO FluNet surveillance data, found that 100 countries have one flu peak season, 13 have two peak seasons, and 5 have year-round flu season. The researchers said that national estimates are useful for planning the purchase of flu vaccine, timing of vaccination, and establishing other policies for managing the disease.

Though flu surveillance in Africa has improved in recent years, there are still large data gaps regarding seasonal flu activity, they said.
Feb 21 PLoS One study

Stewardship / Resistance Scan for Feb 22, 2018

News brief

Study evaluates cost-effectiveness of Clostridium difficile treatments

A systematic review of treatments for Clostridium difficile infection (CDI) yesterday in Infection Control and Hospital Epidemiology concludes that the most cost-effective treatment remains unclear.

The literature review conducted by researchers from the Cleveland Clinic and the University of Texas School of Public Health included 14 studies on economic valuations of various treatment modalities for initial and recurrent CDI. Thirteen of the studies were conducted in high-income countries in the last 5 years, and more than 90% were deemed moderate-to-high or high-quality. Cost of therapy, time horizon, treatment cure rates, and recurrence rates were common influential factors in the study results.

The researchers found that fidaxomicin, a newer CDI drug, appears to be more cost-effective than other therapies, but not definitively. For initial CDI with no specific disease severity, fidaxomicin was found to be more cost-effective than metronidazole and vancomycin in two studies, but not in the study that accounted for severity. Two studies found fidaxomicin to be the most cost-effective treatment for initial severe CDI, but another concluded differently, possibly because of the higher cure rate of vancomycin and the higher cost of fidaxomicin. Three of five studies found that fidaxomicin was cost-effective for treating recurrent CDI.

The group also found that fecal microbiota transplantation (FMT) by colonoscopy was cost-effective for treating recurrent CDI in all four studies that analyzed it. But FMT via other routes was not found to be cost-effective.

The authors of the meta-analysis say that while fidaxomicin and FMT have opened up a new arena in CDI management, the high cost of these treatments (compared with vancomycin and metronidazole) means that further evaluation of their cost-effectiveness is needed. "Our review informs future research of areas that need improvement and may help policymakers and physicians to critically assess the cost-effectiveness of different CDI treatments," they write.
Feb 21 Infect Control Hosp Epidemiol abstract


WHO releases updated guidelines for management of latent TB

Updated guidelines on management of latent tuberculosis infection (LTBI) from the World Health Organization (WHO) call for expanded access to preventive treatment and testing along with new testing and treatment options.

LTBI is defined as a state of persistent immune response to stimulation by Mycobacterium tuberculosis antigens, with no evidence of clinically manifest active TB. People with a latent infection may develop active TB if they don't receive appropriate treatment.

The updated, consolidated guidelines include new recommendations on several different fronts, beginning with who should be prioritized for LTBI testing and preventive treatment. While previous guidelines have prioritized people with HIV and children under the age of 5 who have been in contact with people who have TB, the updated guidelines expand that group to include HIV-negative children, adults, and adolescents who are household contacts of people with bacteriologically confirmed TB. Select household contacts of patients with multidrug-resistant TB are also among those who may be considered for preventive treatment.

The updated guidelines also call for the use of either a tuberculin skin test or an interferon-gamma release assay in LTBI testing but note that such tests are not required for preventive treatment in people with HIV or child household contacts under the age of 5.

For treatment, the guidelines include shorter treatment options. Isoniazid monotherapy for 6 months remains the recommended treatment for children and adults, but rifampicin plus isoniazid daily for 3 months should be offered as an alternative in children and adolescents under the age of 15, and rifapentine plus isoniazid weekly for 3 months may be offered as an alternative for adults and children.
Feb 22 WHO updated guidelines for LTBI management

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