News Scan for Jul 05, 2017

News brief

New Saudi MERS case confirmed as WHO details Lebanese man's illness

Saudi Arabia yesterday reported one new MERS-CoV case, involving a 57-year-old Saudi woman from Hail, and the World Health Organization (WHO) provided a detailed report on a recently announced imported infection detected in Lebanon.

In Saudi Arabia, the woman infected by MERS-CoV (Middle East respiratory syndrome coronavirus) is not a healthcare worker, and the source of the virus is reported as primary, meaning investigators don't think she contracted it from another sick patient. She is in stable condition. Hail is in northwestern Saudi Arabia.

The illness raises Saudi Arabia's overall total from the disease to 1,674 cases, 681 of them fatal. Ten people are still being treated for their infections.
Jul 4 Saudi MOH statement

The WHO, meanwhile, said Lebanon's recent imported MERS-CoV case-patient, announced Jun 28 by the country's health ministry, is a 39-year-old Lebanese man who got sick after arriving from Saudi Arabia on Jun 11, where he worked in healthcare in Riyadh.

As part of enhanced MERS surveillance, a nasopharyngeal swab was taken on Jun 11 in Riyadh, but tests were negative for the virus. Four days after he arrived back in Lebanon, he sought medical care for gastrointestinal symptoms, and a chest x-ray revealed pneumonia. The WHO said a lower respiratory sample collected the next day was positive for the virus.

The man was placed in home isolation, and he has been asymptomatic since Jun 17. Follow-up tests over the next week, including one lower respiratory sample, were negative for MERS-CoV, and the man was released from home isolation. All contacts in Lebanon have tested negative so far.

In Saudi Arabia, authorities are tracing his contacts and the source of infection. Though he is a healthcare worker, he does not work in a facility that treated recent MERS-CoV patients, and he had no known contact with patients infected with the virus. The man doesn't have any underlying health conditions and had no contact with camels in the 2 weeks before he fell ill.

Since the virus was first detected in humans in 2012, the WHO has received reports of 2,037 cases, at least 710 of them fatal. The vast majority of the cases have been in Saudi Arabia.
Jul 4 WHO statement
Jul 3 CIDRAP News story "Lebanon reports imported MERS cases; virus sickens 1 more in Saudi Arabia"


Study finds tick attachment duration similar for new Lyme disease bacteria

A new species of Borrelia that can cause Lyme borreliosis—first identified in 2016—transmits in the same amount of time after a tick bite as the better-known Borrelia burgdorferi, researchers from the US Centers for Disease Control and Prevention (CDC) reported today.

Borrelia mayonii needs 48 or more hours' duration of attachment of a single nymphal blacklegged tick to transmit the bacteria, the CDC team said in their study, published today in the Journal of Medical Entomology, published by the Entomological Society of America (ESA).

The likelihood of transmission rises significantly if attachment duration reaches 72 hours, similar to what is already known about B burgdorferi, previously thought to be the only bacterial species thought to cause Lyme disease.

To assess B mayonii transmission, the researchers examined spread from ticks to mice at four different attachment time intervals: 24, 48, and 72 hours and after full feed. They focused on nymphal ticks, which are more likely to pass the bacteria than larval or adult ones. At 24 and 48 hours of attachment, the investigators found no evidence of transmission, but among mice examined after 72 hours of tick attachment, 31% were infected. The infection rate rose to 57% in mice examined after a tick's complete feed, which lasted between 4 and 5 days.

Lars Eisen, PhD, a CDC entomologist and senior author of the study, said in an ESA press release, "Our findings underscore the importance of finding and removing ticks as soon as possible after they bite."

B mayonii was identified after six patients seen for Lyme disease symptoms at the Mayo Clinic in Rochester, Minn., in 2013 had unusual blood-test results. Eisen said researchers have more to learn about the bacteria, such as its geographic range, how commonly different ages of ticks are infected, and which animals are the natural reservoirs.
Jul 5 J Med Entomol abstract
Jul 5 ESA press release


H5N2 avian flu hits more Taiwanese poultry farms

Taiwan yesterday reported six more highly pathogenic H5N2 outbreaks, all of them involving commercial poultry farms, according to a notification from the World Organization for Animal Health (OIE).

All of the events occurred at locations on the southwest side of the island: three in Yunlin County, two in Tainan City, and one in Pingtung County. The outbreaks began from Jun 22 tl Jun 27, affecting facilities housing ducks, turkeys, native chickens, and geese.

Of 53,085 susceptible birds, the virus killed 5,899, and authorities culled the surviving poultry to curb the spread of the virus.

Taiwan has been battling H5N2 and other avian flu strains since early 2015.
Jul 4 OIE report

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