ProMED-mail |

Published Date: 2011-06-03 20:25:27
Subject: PRO/EDR> Respiratory syncytial virus - Chile: (Santiago)
Archive Number: 20110603.1699

RESPIRATORY SYNCYTIAL VIRUS - CHILE: (SANTIAGO)
***********************************************

A ProMED-mail post
http://www.promedmail.org
ProMED-mail is a program of the
International Society for Infectious Diseases
http://www.isid.org

Date: Fri 3 Jun 2011
Source: terra [in Spanish, machine trans., edited]
http://www.terra.cl/zonamujer/index.cfm?id_cat=2007&id_reg=1663537

Poor air quality exacerbates respiratory syncytial virus outbreak
-----------------------------------------------------------------
Cases of respiratory syncytial virus (RSV) infection have appeared
earlier this year [2011]. Since the beginning of May there has been a
substantial increase in the number of cases, and during week 21 [the
week ending 29 May 2011] reached more than 320 [in Santiago]. This is
close to the peak number of cases observed in 2010, which was in the
month of July, that is a month [sic] later.

Poor air quality, accompanied by lack of rain, low temperatures, and
poor ventilation in living accommodations, has exacerbated the
situation and advanced the onset of seasonal RSV infection in
children. Public health clinics are being overburdened by
consultations and the more severe cases are causing problems in
intensive care units (ICU).

Dr Jorge Roque, head of the pediatric ICU at the German Clinic,
explained that every year we have an outbreak of respiratory syncytial
virus infection, but the dates do not always correspond. "This year
[2011] in week 21 [the week ending 29 May 2011], we are reaching
levels very close to what we had in June last year [2010], giving the
impression that we are in a crisis situation. Probably in 1 or 2 weeks
we will be at the peak and case numbers will begin to decline, and the
RSV season will terminate earlier.

Last year [2011] there were between 380 or 400 cases whereas this
week [week of 1 Jun 2011] we have 320 cases already and we are rapidly
approaching the peak, which may last a week or 2 and then begins to
decline. During this period we are somewhat stressed, because for
example at the German Clinic, nearly half of the 12 beds in the
Intensive Care Unit are occupied by children with RSV infection."

One consequence of environmental pollution is that that the air is
drier and "sudden temperature changes can occur causing hyperactivity,
which in children, especially in infants under 6 months and in
children with chronic respiratory diseases like asthma, exacerbates
the situation."

Nationally, parainfluenza viruses and adenoviruses are significant
causes of respiratory illness in children, "but RSV is the main public
health problem. Environmental conditions, such as low temperatures and
air pollution in Santiago, may trigger outbreaks earlier -- as in this
year [2011] -- and influence the behavior of viruses and infections in
general."

--
Communicated by:
HealthMap Alerts via ProMED-mail
<promed@promedmail.org>

[RSV can cause upper respiratory infections and lower respiratory
tract infections (such as bronchiolitis and pneumonia). In children
under 1 year of age, RSV is the most important cause of bronchiolitis,
an inflammation of the small airways in the lung. Almost all children
will have had an RSV infection by their 2nd birthday. When infants and
children are exposed to RSV for the 1st time, 25 percent to 40 percent
of them have signs or symptoms of bronchiolitis or pneumonia, and 0.5
percent to 2 percent will require hospitalization. Most children
hospitalized for RSV infection are under 6 months of age.

Infants and children infected with RSV usually show symptoms within 4
to 6 days of infection. Most will recover in 1 to 2 weeks. However,
even after recovery, very young infants and children with weakened
immune systems can continue to spread the virus for 1 to 3 weeks.

People of any age can get another RSV infection, but later infections
are generally less severe. The elderly and adults with chronic heart
or lung disease or with immune systems weakened by medical conditions
or treatments remain at high risk for developing severe RSV disease if
reinfected.

In temperate climates, RSV infections generally occur during fall,
winter, and early spring. As recorded in the report above from
Santiago, Chile, the timing and severity of RSV circulation in a given
community can vary from year to year. In the southern hemisphere the
winter epidemic of RSV normally occurs in May/June/July, and during
November/December/January in the northern hemisphere.

For further information see
http://www.cdc.gov/rsv/about/infection.html.

The location of the city of Santiago can be seen on the
HealthMap/ProMED-mail interactive map of Chile at
http://healthmap.org/r/0WJ1. - Mod.CP]

See Also