Flu Scan for Aug 08, 2018

News brief

WHO says Southern Hemisphere flu activity remains fairly low

Influenza activity remains elevated in South America, has started to decline in southern Africa, and is still below seasonal threshold levels in Australia and New Zealand, the World Health Organization (WHO) said in its latest update.

Samples testing positive for influenza in Chile and Paraguay have increased, the WHO said, with the H3N2 strain dominating in Chile. Flu has declined in Brazil, however, and remains low in Argentina. Flu activity has also declined in Colombia and Peru but remains elevated. 2009 H1N1 is the predominant strain in southern Africa as activity drops there.

Flu activity remains low in Australia and New Zealand, but influenza-like illness in West Australia is rising and appears to have crossed the seasonal threshold. H1N1 is the predominant strain in Oceania, which includes Australia and New Zealand.

Northern Hemisphere flu activity remains at inter-seasonal levels, the WHO said.

Analysis of FluNet isolates from the most recent week of data shows that 88% of viruses are influenza A. Of flu A viruses subtyped, 76% were H1N1.
Aug 6 WHO update

 

Study shows mismatch between flu vaccine, circulating strains common

In an illustration of how commonly mismatch occurs between flu vaccine strains and circulating flu viruses, Hong Kong investigators used 17 years' of data to determine that a close match occurs only 11% to 21% of the time, depending on the strain and vaccine.

The researchers analyzed data from 1996 through 2012 in Hong Kong, focusing on H3N2 (one of the two major "A" strains) and influenza B, because changes in vaccine composition were more frequent for those viruses. They sequenced an average of 30 clinical samples of influenza H3N2 and 30 of influenza B per year, except for 2009, when influenza H1N1 predominated. They divided the 17-year period into 34 flu seasons—winter and summer for each year.

The researchers found that Northern Hemisphere vaccine strains were closely matched with circulating strains for 7 (20.6%) of 34 seasons for H3N2 and 5 (14.7%) of 34 seasons for influenza B. For the Southern Hemisphere vaccine, the rates were 14.7% for H3N2 and 11.1% for influenza B.

Strain drift among seasons was 41.2% for H3N2 and 35.3% for influenza B. In addition, biannual vaccination strategy—administering Northern Hemisphere vaccines in November followed by Southern Hemisphere vaccines in May—did not improve match rates.

The authors conclude, "A specific strategy is urgently needed to select and produce influenza vaccines targeting the tropical and subtropical regions."
Aug 7 Emerg Infect Dis study

News Scan for Aug 08, 2018

News brief

Vaccination begins in DRC Ebola outbreak; tests confirm 1 more case

One week after the Democratic Republic of the Congo's (DRC's) health ministry declared a new outbreak in the east of the country, an immunization campaign began today, which targeted frontline health workers from the Mangina Reference Health Center, the epicenter of the outbreak, who had been in contact with confirmed cases and their contacts.

Vaccinators were Congolese workers who had been trained by teams from Guinea during the Equateur province outbreak, which was declared over in late July, according to a health ministry statement. Several teams from Guinea will return to the DRC to help with vaccination in the latest outbreak.

DRC Health Minister Oly Ilunga, MD, visited the Mangina outbreak areas today, and the provincial health minister and province's immunization coordinator were among the first to be vaccinated, a step done to reassure residents about the safety of the vaccine.

In other outbreak developments, one more Ebola case was confirmed. The overall total is now 44, which included 17 confirmed and 27 probable cases. Health officials are investigating an additional 47 cases. So far 36 deaths have been reported.
Aug 8 DRC health ministry statement  

 

WHO details 2 vaccine-derived poliovirus outbreaks in Nigeria

The World Health Organization (WHO) said today that Nigeria is experiencing two separate circulating vaccine-derived poliovirus type 2 (cVDPV2) outbreaks.

One of the events is based on 10 environmental samples collected from Jan 30 to May 23 from two collection sites in Sokoto state, according to the WHO statement. So far no associated cases of acute flaccid paralysis (AFP) have been found that are related to the environmental detections.

In a separate outbreak, cVDPV2 was found in a stool sample from a patient in Yobe state and in an environmental sample collected on May 31. The patient's AFP symptoms began on Jun 16. The WHO said the same virus was found in Gombe state from an environmental sample collected on Apr 9 and in Jigawa state from an AFP patient whose symptoms began Apr 15 and in six environmental samples collected from Jan 10 to May 2.

Detailed investigations were conducted following the detection of the AFP cases and environmental positives. In response to the dual outbreaks, health officials conducted a vaccination drive with monovalent oral type 2 vaccine that targeted 54 local government areas in Jigwa, Bauchi, Gombe, and Sokoto states. Other response steps include enhanced surveillance and stepped-up routine immunization activities.

A WHO risk assessment done before the outbreak response started determined a high risk of spread of the two outbreak virus strains. The agency urges countries, especially those with frequent travel to and contacts with polio-affected countries, to strengthen their surveillance for AFP and maintain high vaccination coverage.
Aug 8 WHO outbreak statement

 

Italy moves to overturn mandatory childhood vaccinations

Despite an increase in measles outbreaks, Italy's upper house of government voted this week to eliminate a law that requires children to have 10 common vaccines before starting school.

According to the British newspaper The Independent,the law was put in place in March after 4 people died and 5,000 were infected in a nationwide measles outbreak. At that time, only four vaccines, not including the measles, mumps, and rubella vaccine, were required before school admittance.

But growing pressure from a strong anti-vaccine movement led the Five Star Movement and the League (two political parties) led the upper house to take up the legislation.

Deputy prime minister and leader of the League, Matteo Salvini, said that having 10 compulsory vaccines is "useless and sometimes dangerous," according to the story.

The 10-vaccine law stands, however, until a forthcoming lower house vote.
Aug 7 Independent story

 

WHO officially declares India's 19-case Nipah outbreak over

The Nipah outbreak in India's Kerala state appears to be over, as there have been no new deaths or cases reported since Jun 1, according to an update from the WHO yesterday. As noted previously, a total of 19 people contracted the virus, and there were 17 deaths attributed to the deadly emerging infectious disease.

Only two patients recovered completely and have been discharged from the hospital. The outbreak affected only Kerala, where the earliest patients in May first became sick after entering a well that was populated with fruit bats.

"Acute respiratory distress syndrome and encephalitis were observed among the patients infected. This was the first NiV outbreak reported in Kerala State and the third NiV outbreak known to have occurred in India; the two previous outbreaks occurred in the state of West Bengal in 2001 and 2007," said the WHO.

The WHO estimates Nipah's case-fatality rate to be between 40% and 75%. Though human-to-human transmission can occur, the disease is most commonly spread via consumption of fruit contaminated by the saliva of infected bats, or from direct contact with infected bats or their feces or urine. There are no treatments available for Nipah.
Aug 7 WHO update

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