Meta-analysis confirms Zika triggers GBS
A new study published today in PLOS Medicine shows that the Zika virus triggers Guillain-Barre syndrome (GBS) and causes congenial birth defects. Though these findings have been demonstrated by other studies, this is the largest systemic literature review of the most devastating outcomes of Zika infection to date.
The authors of the study developed a causality framework for Zika virus and congenital brain defects and GBS after the World Health Organization (WHO) declared Zika virus a public health emergency of international concern in February of 2016. The authors reviewed all Zika literature published on or before May 30, 2016, and had a panel of experts assess the findings for evidence of causality.
The experts, members of a WHO working group on the topic, reviewed 72 studies concerning Zika and congenital birth defects and 36 studies that looked at the mosquito-borne disease and GBS. The experts said there was more research, and thus evidence, concerning Zika and congenital defects as microcephaly was a more public and unknown consequence of Zika infection, while GBS is a known post-infection outcome of several diseases.
The authors suggest that Zika is a ripe disease for a "living systemic review," as new data will continuously inform and change the understanding of the disease during this current outbreak.
"We are working on methods to produce a living systematic review of the Zika causality framework that will incorporate new studies, provide frequent open access updates, and allow cumulative meta-analyses of both aggregate and individual patient data from rigorous prospective studies as these become available," the authors concluded.
Jan 3 PLOS Med study
Officials report 3 new MERS cases and 3 deaths in Saudi Arabia
Over the New Year's weekend, Saudi Arabia's Ministry of Health (MOH) reported three new MERS-CoV cases and three deaths, two of them in previously reported patients. Two of the three new cases had direct contact with camels.
On Dec 31, a 49-year-old Saudi male from Al Khurma was diagnosed as having Middle East respiratory syndrome coronavirus (MERS-CoV). The man had direct contact with camels, a known risk factor for contracting the virus. He is in stable condition. On Jan 1, a 44-year-old Saudi man from Riyadh died from the respiratory illness.
Yesterday a 70-year-old Saudi man from Medina was diagnosed as having MERS-CoV. He is in stable condition and had contact with camels. Also yesterday, a 63-year-old Saudi woman from Buraidah was diagnosed as having MERS-CoV and also listed as deceased from the disease. And a 50-year-old Saudi man from Khamis Mushait also died.
Flu vaccine protection wanes throughout season
A new study published recently in the journal Clinical Infectious Diseases shows that the protection influenza vaccines offer patients wanes throughout the course of the flu season by as much as 10% each month.
The study used data pooled by the US Influenza Vaccine Effectiveness Network from the 2011-2012 season through the 2014-2015 season. Outcome was defined as confirmed influenza infection in relation to days between vaccination and symptom onset. All patients were age 9 years or older.
Protection from both influenza A and B viruses decreased at a rate of about 7% per month for influenza A (H3N2) and B. In 2009, H1N1 protection decreased between 6 to 11% per month. Patients who received the flu vaccine before the current season began had a more pronounced drop in vaccine effectiveness. The vaccine offered some protection for at least 5 to 6 months for all strains.
The authors suggest their study confirms previous findings that show patterns of increasing influenza risk in vaccinated populations over time, but admit bias could partially explain their findings.
Dec 29 Clin Infect Dis study
China reports 2 more H7N9 avian flu cases
Two of China's provinces reported two new H7N9 avian flu cases over the past few days, raising the number of infections in the fifth wave of disease activity to 21.
On Jan 1 the government media reported a case in Guizhou province in south-central China, according to reports translated and posted by FluTrackers, an infectious disease news message board. The patient is 49 years old and was hospitalized on Dec 27, then transferred and placed in isolation on Dec 29. The report suggests that the patient is a poultry seller.
The second case was reported in Jiangxi province in southeastern China. A statement today from Hong Kong's Centre for Health Protection (CHP) said the patient is a 53-year-old man from Jingdezhen who is hospitalized in critical condition in Nanchang.
The new cases lift the overall global total from H7N9 since it was first detected in humans in 2013 to 829, according to a case list kept by FluTrackers.
Jan 1 FluTrackers thread on Guizhou province case
Jan 3 CHP statement
FluTrackers H7N9 case list
PAHO reports small increase in chikungunya cases
The Pan American Health Organization (PAHO) reported only 108 new suspected, confirmed, and imported chikungunya cases late last week, after reporting more than 56,000 new infections the week before.
A smattering of cases in a handful of countries accounted for the increase, with Colombia and Costa Rica each reporting 20 new cases to top other nations, according to the Dec 30 update. Most countries, however, have not reported new cases for several weeks. Brazil, which has accounted for 82% of all cases in 2016 and was responsible for the big jump in cases in the Dec 23 update, has yet to report on the final 3 weeks of the year.
Countries in the Americas have now reported 498,290 suspected, confirmed, and imported chikungunya cases this year. The outbreak began in late 2013 on the Caribbean island of St. Martin and has now sickened 2,376,730 people.
Dec 30 PAHO update