For the past several days Spanish media in Catalonia - in the Northeast of Spain - has been reporting on a growing number of children hospitalized with neurological symptoms associated with enterovirus infection.
The outbreak appears to have started in the middle of April, and has affected at least 60 children, with today's reports saying 29 are currently hospitalized.
An English language report from El PAIS, posted today:
A total of 60 minors in Catalonia have been infected, and two remain in serious condition
An outbreak of an enterovirus that can cause severe illness has already affected 60 children in Catalonia, according to the most recent figures released by the regional health department.
Of these, 29 were hospitalized after suffering a form of encephalitis, which causes inflammation of the brain stem and cerebellum. Health authorities said most of the children are recovering well, although two remain in a serious condition.
Similar outbreaks have been reported in Bulgaria, the United States and several Asian countries, but this is the first time Spain has experienced so many cases at the same time.
It’s behaving differently from what we usually see, and it is hard to know what to expect - Carles Rodrigo, Vall d'Hebron Hospital chief of pediatrics
Experts have ruled out the presence of EV-D68 in all 48 cases reported since April 13, when the first case arrived at the emergency room of Vall d’Hebron Hospital in Barcelona. That child, who went into cardiac arrest, remains in hospital with “serious effects,” according to Carles Rodrigo, head of pediatrics at the hospital. Most of the other cases were reported in May.
Other (Spanish language) reports suggest the culprit may be EV-71, as does this one from El PAIS.
The first results of the Microbiology Department of Vall d'Hebron on Thursday revealed that serotype detected in two patients is the A71, a strain that particularly affects the central nervous system and causes romboencefalitis. In 15 cases, the microbiological studies have also found that it is an enterovirus group A, despite missing serotype specify what exactly that will be announced in the coming days.
Hopefully we'll get clarification from the ECDC or some other official source in the next few days. There is no mention of this outbreak in the most recent Communicable disease threats report from the ECDC.
Assuming for the moment that the cause is EV-71 . . . .
Human Enterovirus 71 (EV-71) – which is most often reported in Asia and the Western Pacific region - is one of more than 60 non-polio enteroviruses (NPEVs) known to cause cause human illness, and that primarily affect children under the age of 10.
While EV-71 is most frequently linked to severe outbreaks of HFMD (Hand, Foot, & Mouth Disease), it is also capable of producing serious neurological illnesses – including poliomyelitis-like paralysis (AFD or Acute Flaccid Paralysis), encephalitis, and sometimes death.
In 2012, we saw an outbreak of EV-71 in Cambodia that claimed the lives of dozens of children (see Updating The Cambodian EV71 Story), while a year later in Australia: Acute Flaccid Paralysis & EV71, we looked at a report that described 5 cases of acute flaccid paralysis (AFP) in children who tested positive for the EV71 virus.
Although EV-71 was first described in a California infection in 1969, and outbreaks of EV-71 associated HFMD were recorded in Europe, North America, and Australia back in the 1970s (see BMJ article on Challenges of EV-71) the genotypes circulating in Asia today have evolved to become more virulent than those of 40 years ago.
As with many other infectious diseases, there are genuine concerns that EV-71 may, through repeated introductions via international travel, spread beyond Asia and the Pacific to get a foothold in Europe and North America.
As we saw two summers ago with EV-D68, when introduced into an immunologically naive population, enteroviruses have the potential to spread rapidly.
While large EV-71 outbreaks have not occurred outside of Asia yet, there is no good reason why they couldn’t in the future. So we'll keep an eye on this outbreak, and any signs it may be spreading beyond Catalonia.