Saturday, April 09, 2016

Unseasonable Seasonal Flu In São Paulo

# 11, 247

For São Paulo, Brazil's largest city (pop. 20 million), April signals the end of summer and the start of slightly cooler and drier weather.  Sitting on the Tropic of Capricorn, it lies on the cusp between the tropic and temperate zones, but due to its altitude (600m), its climate tends to be moderate. 

Although influenza circulates at low levels pretty much year-round in more tropical regions of Brazil, in São Paulo, one would expect flu season to begin in May, and peak sometime in June, July, or August. 

This year, however, the pattern appears to be different, and because of that the São Paulo Secretaria de Estado da Saúde has started their yearly flu vaccination campaign earlier than normal.

The headline and the lede from an AP report in the Washington Post earlier this week, explains why.

Brazil: Swine flu has killed twice as many people as in 2015

SAO PAULO — The H1N1 swine flu virus has killed almost twice as many people in Latin America’s biggest country over the past three months as it did in all of 2015, Brazil’s Health Ministry said Tuesday.
The ministry said the illness caused 71 deaths in January, February and March, compared to 36 in 2015.

Of the 71 deaths, 55 were in the state of Sao Paulo, which accounted for 372 of the 444 cases registered in the first three months of the year.

There are, admittedly, a few problems with this report.

First, calling what is now seasonal H1N1 (ok, technically H1N1pdm09`Swine Flu' is so 2009 (but good for ratings), and second, deaths from influenza are notoriously under counted, making the 2015 total of 36 H1N1 deaths highly suspect, even though it was predominantly an H3N2 year.

And there's likely a degree reporting bias this year over last, given Brazil's Zika crisis and the Olympics four months from now. 

But there does seem to be an unseasonable summer surge in H1N1 in São Paulo this year. And that, combined with other reports of unusual H1N1 activity this winter (see ECDC Risk Assessment : Reports Of Severe A(H1N1)pdm09 In Europe) and the upcoming Olympics, has SP's Public Health sector scrambling. 

This from the São Paulo State Department of Health.

SP starts vaccinating 530,000 health professionals flu

2016 campaign opening will be held at the Hospital Central Institute; public and private hospitals of employees in the capital and Greater São Paulo will be immunized  

The Secretariat of Health of São Paulo held this Monday, April 4, the opening of the early campaign of vaccination against influenza in the hall of the Hospital of the Central Institute of the FMUSP (Faculty of Medicine, University of São Paulo) .
The event marks the beginning of immunization of 532,400 health professionals from public and private hospitals in the capital and metropolitan region of Greater São Paulo, which occurs in the first week of the campaign. Between 4 and 8 April, all health services in the municipalities in the region will receive the doses to carry out internal campaigns.
Immunization of health professionals is the first measure envisaged in anticipation of the flu vaccination organized by the Ministry of Health. The population will be vaccinated gradually, starting with the priority groups. In this first stage of the 2016 campaign, 3.5 million Paulistas receive doses that protect against viruses Winter 2016 (A / California (H1N1), A / Hong Kong (H3N2) and B / Brisbane).
From April 11, the vaccination will be extended to other priority groups: children over six months and under five years (982 800), pregnant women (179,000) and the elderly (1.83 million) of capital and Greater São Paulo, totaling nearly 3 million people protected against viruses.
For the other cities in the state and other audiences (chronically ill, mothers, indigenous, employees of prisons and prisoners), the vaccination campaign against influenza should follow the Ministry of Health Calendar, commencing for April 30.
"Initially Vaccinating health care professionals is essential to protect them due to direct contact with a large number of people who can be with the virus. We need to ensure the integrity of the health of these professionals to continue offering adequate care to patients. Following, the focus will immunize children, pregnant women and the elderly, as these priority groups are more susceptible to disease worsening, "said Secretary of Health of São Paulo, David IPU.
The State of São Paulo intensified population protection measures since March 23, when initiated extra vaccination in 67 municipalities of São José do Rio Preto region, using remaining doses of 2015. The strengthening of immunization is due to the prevalence of the number of cases in this area, compared to the total state territory. Still, all the inhabitants of those cities that take this vaccine should also be vaccinated during the national campaign in 2016, as the doses have different compositions.
This year, until March 29, it was reported 465 cases and 59 deaths from SARS in São Paulo attributable to influenza virus. Of this total, 372 cases and 55 deaths were related to the A (H1N1) virus; on the virus B were 32 reported cases and 2 deaths. In 2015, 342 cases of SARS have been reported throughout the state, and 190 related to the type A (H3N2) and B. 43 to the total of virus 65 deaths recorded in 2015, 28 were also related to the A (H3N2) and 10 with B 
The distributed flu vaccine in the public network is produced by Instituto Butantan unit connected to the folder through a technology transfer process. 

Posted by Press Office on

Whether the product of increased surveillance, an overly hyperbolic press, or an actual change in the behavior or virulence of the H1N1 virus, the reports out of Brazil are unusual enough to warrant watching.

Seasonal influenza viruses continually mutate, and while major changes in virulence are rare, they are not unheard of. 

And just as with the Hajj, the World Cup, and the Super Bowl, the Olympics brings both unique local public health challenges and the potential to disseminate infectious diseases around the globe (see The International Exchange Rate Of Infectious Diseases).

All of which provides us with one more reason (as if we needed it) to keep an eye on Brazil in the months ahead.

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