News Scan for Nov 21, 2013

News brief

Saudi Arabia reports another fatal MERS-CoV case

A 37-year-old Riyadh resident has died of Middle East respiratory syndrome coronavirus (MERS-CoV) infection, according to a brief translated statement from the Saudi Arabian health ministry today.

The machine-translated statement says the patient was a citizen but gives no information on the duration or course of illness, possible exposures, or investigation of contacts. It was posted on the Avian Flu Diary blog by Michael Coston.

With the report, the health ministry's MERS-CoV count has increased to 130 cases with 55 deaths. The World Health Organization had not yet confirmed the case at this writing.
Nov 21 Avian Flu Diary post
Saudi health ministry page with case count

 

New York county reports locally acquired dengue case

Officials yesterday reported the first case ever of locally acquired dengue in New York State, in Suffolk County on Long Island.

Suffolk County Commissioner of Health Services James Tomarken, MD, MPH, said a man older than 50 from Babylon Township was hospitalized in September with symptoms consistent with dengue infection but has since fully recovered, according to a Suffolk County Health Services (SCHS) news release.

Suffolk County had two confirmed dengue cases in 2012 and three in 2011, but those patients are thought to have acquired the virus while traveling in dengue-endemic regions, the release said.

"We have determined that this individual acquired dengue virus locally, as he had not traveled outside of the local metropolitan area during the incubation period," Tomarken said.

The man was likely infected when bitten by a mosquito that had previously bitten an infected traveler, the SCHS release noted. Health officials said they don't expect dengue to become widespread in the temperate state.

"Given the recent introduction of Aedes albopictus [mosquitoes] into New York State and the high level of travel in New York to areas of the world endemic for dengue, it is not surprising that a locally acquired case of dengue has been found in the state," said State Health Commissioner Nirav R. Shah, MD, MPH.

Earlier this week Texas reported 18 dengue cases, 7 of which were thought to be locally acquired, and Florida so far this year has confirmed 23 locally acquired cases.
Nov 20 SCHS news release
Nov 19 CIDRAP News scan,
"Southern Texas counties report 18 dengue cases"

 

Analysis of H7N9 reveals time and location clusters

An analysis of the location and timing of cases reported in China's H7N9 avian flu outbreak this spring found that the event occurred in three stages, which may have been affected by weather conditions, researchers from China and Sweden reported today.

Their Eurosurveillance report covers 131 cases that were reported from Mar 28 through May 31. Most of the cases occurred in eastern coastal provinces of Zhejiang, Shanghai, and Jiangsu. The main cluster included 30 counties in Zhejiang from early to mid April, while two secondary ones in March and April spanned 21 counties near the Shanghai-Jiangsu boundary.

In the first 4 weeks the outbreak was highly sporadic, followed by a high-incidence peak that occurred over the next 5 weeks that included 76% of the cases. The late-stationary period lasted 6 weeks, marked by transmission control efforts that were associated with the end of the outbreak in the hardest-hit areas.

The group reported that winter temperatures start rising in China in late February and that the months of March and April are relatively warm, with hot weather beginning in May. They wrote that the spike in cases in March and April might suggest that the mild temperatures were suitable for H7N9 infection. "If there is a relationship, attention must be paid as there could be a potential outbreak in the same period (March-April) in the future," according to the report.

More studies are needed to look at the risk factors, such as poultry density, that contributed to the patterns, but the current findings suggest human population density didn't influence the infection pattern, the group noted.
Nov 21 Eurosurveill study

 

Study: Rotavirus vaccine reduces seizures in kids by about 20%

Vaccination against rotavirus, a common cause of diarrhea and vomiting in children, appears to have an additional benefit—reduction of related seizures to the tune of $7 million in potential healthcare cost savings—according to a study yesterday in Clinical Infectious Diseases, published by the Infectious Diseases Society of America (IDSA).

The authors, from the US Centers for Disease Control and Prevention (CDC) and several other institutions, retrospectively studied data from the Vaccine Safety Datalink project on children born after rotavirus vaccine was licensed in the United States (Feb 28, 2006) through November 2009 to determine the incidence of seizures 4 to 55 weeks after full rotavirus vaccination and compare it with the incidence in nonvaccinated children.

Among the entire cohort of 250,601 infants, 186,502 (74.4%) had been fully vaccinated against rotavirus, defined as three doses of RotaTeq or two doses of Rotarix.

The researchers found that rotavirus vaccination was statistically associated with an approximate reduction in seizures requiring hospitalization or emergency department care of 18% to 21% as compared with nonvaccination. After adjusting for covariates, a statistically significant protective association of vaccination was seen for both first-ever seizures (risk ratio [RR] = 0.82; 95% confidence interval [CI], .73 to .91) and all seizures (RR = 0.79; 95% CI, .71 to .88).

Pediatrician Geoffrey Weinberg, MD, of the University of Rochester School of Medicine and Dentistry, said in an accompanying commentary that even given study limitations and potential confounding factors, "Work such as this not only is interesting scientifically, but provides yet another reason to strongly promote universal rotavirus immunization. In addition, the work provides us an opportunity to reflect on the fact that sometimes, unexpected effects of vaccination are beneficial and are a cause for celebration, rather than the more commonly publicized concern for unexpected adverse effects."
Nov 20 Clin Infect Dis article abstract
Nov 20 Clin Infect Dis commentary extract
Nov 21 IDSA press release on the study

Report notes China's fast response to polio outbreak in 2011

An outbreak of imported wild-type poliovirus in 2011 in China's Xinjiang province was stopped a month and a half after lab confirmation of the index case, according to a report on the investigation of and response to the outbreak published today in the New England Journal of Medicine.

A level 2 public health emergency response, the highest level authorized, was instituted within days of confirmation of polio in the index case. Intensified surveillance, supplementary vaccination programs that eventually included administration of 43.7 million oral polio vaccine doses, and public education efforts were key parts of that response. The outbreak involved 21 cases of infection and 23 clinically compatible cases.

An accompanying editorial says, "Public health authorities in China are to be commended for containing the outbreak so quickly" but points out the considerable cost of China's efforts, the difficulty in launching such a response so rapidly in other countries experiencing outbreaks currently, such as Syria, and strategic plans of the Global Polio Eradication Initiative to eradicate the disease worldwide by 2018.

The authors of the report conclude that even countries certified as polio-free, a group to which China was added in 2000, remain at risk as long as there is poliovirus circulating anywhere in the world.
Nov 21 N Engl J Med abstract
Nov 21 N Engl J Med editorial

 

CDC reports on human metapneumovirus outbreaks in nursing homes

Two human metapneumovirus (hMPV) outbreaks in nursing homes last year caused severe illness and deaths and pointed up the importance of considering the virus as a possible cause of respiratory disease outbreaks in such facilities, the CDC reported today.

The outbreaks occurred in skilled nursing facilities (SNFs) in West Virginia and Idaho in the winter of 2012, sickening 57 residents. Forty-five (79%) of them had lower respiratory tract infections, 25 (56%) had radiologically confirmed pneumonia, and 6 (11%) died, the CDC reported in Morbidity and Mortality Weekly Report (MMWR).

In both outbreaks, molecular diagnostic testing at a state lab or the CDC was required after tests for influenza and other common respiratory pathogens were negative.

"Clinicians should consider hMPV infection in the differential diagnosis of illness in patients with respiratory tract infection in SNFs, particularly when clusters of severe unexplained respiratory infections are detected," the report says.

Human MPV was first identified in the Netherlands in 2001, according to the CDC. It causes an estimated 5% to 15% of hospitalizations for lower respiratory tract infections in infants and young children, and it can cause symptomatic re-infections throughout life, especially in older and immunocompromised persons. Cases typically peak in late winter and early spring.
Nov 22 MMWR article

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