News Scan for May 17, 2018

More lettuce E coli cases
Exemptions for N95 respirators
Salmonella in pet pythons
Polio in Somalia

E coli outbreak grows to 172 cases but romaine OK to eat, US officials say

Federal officials have added 23 cases and three newly affected states to a multistate outbreak of Escherichia coli cases linked to romaine lettuce and gave what amounts to an all-clear to resume eating the lettuce, according to updates yesterday.

New outbreak totals are 172 cases in 32 states, 75 hospitalizations, and 1 death, the Centers for Disease Control and Prevention (CDC) said in an update. Twenty patients developed hemolytic uremic syndrome, a type of kidney failure, which is 3 more cases than reported in the CDC's previous update on May 9.

The newly affected states are Iowa, Nebraska, and Oregon. California has logged the most cases, at 39, followed by Pennsylvania (21), Minnesota (12), and Idaho (11).

Patients range in age from 1 to 88 years, with a median age of 29. Illness-onset dates range from Mar 13 to May 2. The implicated lettuce was grown in the Yuma, Ariz., growing region.

The Food and Drug Administration (FDA) said in its update, "The FDA has received confirmation from the Arizona Leafy Greens Marketing Agreement administered by the Arizona Department of Agriculture that romaine lettuce is no longer being produced and distributed from the Yuma growing region and that the last date of harvest was April 16, 2018. It is unlikely that any romaine lettuce from the Yuma growing region is still available in stores or restaurants due to its 21-day shelf life."

The CDC said, "This investigation is ongoing, and CDC will provide updates when more information is available."
May 16 CDC update
May 16 FDA update


FDA to exempt certain N95 respirators from premarket requirements

Effective today, the FDA is exempting certain N95 respirators—facemasks that are used in disease settings, including epidemics and pandemics, to protect both the patient and healthcare provider from airborne pathogens—from premarket requirements, the agency said in a statement yesterday.

The FDA and the CDC's National Institute for Occupational Safety and Health (NIOSH) share regulatory oversight of N95 respirators. In final order published today in the Federal Register, the FDA exempted the N95s from premarket notification (510[k]) requirements, and executed a Memorandum of Understanding (MOU) with NIOSH.

The FDA said, "The final order and MOU streamline the regulation of N95s to help manufacturers easily identify, understand, and work to meet marketing requirements, and help ensure the availability of safe and effective medical products, particularly during times of increased demand, such as a public health emergency. This final action will also decrease regulatory burden on the medical device industry and will eliminate costs required to comply with certain Federal regulations."

NIOSH will first evaluate manufacturers' applications to see if they pass the criteria for exemption. It will consider several factors, including whether a specific N95 has had a history of misleading claims or risks, characteristics that might make it unsafe, and any changes in the device that could affect safety or effectiveness.
May 16 FDA statement
May 17 Federal Register notice
FDA-NIOSH Memorandum of Understanding


CDC: Ball python Salmonella cluster sickened people in 4 states

Though the tame nature and smaller size of ball pythons make them popular pets, the snakes can harbor multiple Salmonella strains, the CDC warned today, based on a recent investigation into a cluster of five closely related isolates identified though PulseNet, the national subtyping network.

In July 2017, the network identified five matching Salmonella Paratyphi B variant L (+) tartrate + (Java) clinical isolates from four states, researchers noted in a report in Morbidity and Mortality Weekly Report (MMWR). Two unrelated patients were from Indiana, with Arizona, Oklahoma, and Oregon each reporting a single case. Investigations by state and local health department found that all five patients had been exposed to snakes, with four having ball pythons in their homes.

Sampling at the Arizona patient's house found the outbreak strain in a ball python bedding sample, along with another Salmonella strain from a feeder rodent and the snake. Environmental sampling in Oregon turned up yet another Salmonella strain, and testing at the National Veterinary Services Laboratory identified three Salmonella Paratyphi B variant L (+) tartrate + (Java) isolates from other pythons in 2017.

Whole-genome sequencing of the human isolates found that only the two Indiana patient samples were related, though ball python bedding samples matched the Arizona patient's samples and the Indiana ball python and environmental samples were closely related to both patient samples.

The CDC said that, as with other reptiles, ball pythons are known to carry Salmonella, a fact that has driven its warning that children younger than 5 should avoid contact with the animals. The report's authors noted, however, that the median age in the ball python cluster was 10 years, suggesting that older children are also at risk of illness.
May 18 MMWR report


Type 3 poliovirus samples detected in Mogadishu, Somalia

Health officials in Somalia confirmed the detection of vaccine-derived poliovirus type 3 in four environmental samples collected from two sites near Mogadishu, Somalia, in March. The World Health Organization (WHO) today released a notification on the detection, updating information on the Horn of Africa.

Earlier this year, Somalia reported the detection of vaccine-derived poliovirus type 2 in environmental samples from Mogadishu and Nairobi, Kenya, but no acute flaccid paralysis cases linked to these virus types have been reported.

The WHO said countries in the region are upping surveillance and vaccination efforts in the wake of the detections.

"In Somalia, three large-scale supplementary immunization activities (SIAs) have been implemented in Banadir, Lower Shabelle and Middle Shabelle regions; additional SIAs are planned other affected areas in the Horn of Africa in May," the WHO said. "Intensified surveillance activities are being undertaken to determine the origin of the viral circulation."
May 17 WHO

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