Vol. 58 / No. 17 MMWR 467
to treatment, although relevant evaluations of this approach 8. Kahn RH, Peterman TA, Arno J, Coursey EJ, Berman SM. Identifying
are just beginning. Increasing the use of STD clinics, which likely syphilis transmitters: implications for control and evaluation. Sex
Transm Dis 2006;33:630–5.
were associated with shorter time to treatment than other set- 9. Beltrami J, Weinstock HS. Primary and secondary syphilis among men
tings, especially emergency departments, might decrease time who have sex with men in the United States, 2005. Paper presented
to treatment. All health-care providers who suspect primary at 17th International Society for STD Research. Seattle, WA: July
29–August 1, 2007.
syphilis in a patient should presumptively treat for it at the 10. Cates W. Estimates of the incidence and prevalence of sexually transmit-
time of examination (4). ted diseases in the United States. American Social Health Association
The findings in this report are subject to at least three Panel. Sex Transm Dis 1999;26(4 Suppl):S2–7.
limitations. First, underreporting was likely because report-
ing depends on patients seeking care, health-care providers
diagnosing syphilis, and reporting to the health department.
An estimated 20% of syphilis infections are never diagnosed or Outbreak of Swine-Origin
reported (10). Second, although JCDH attempted to conduct Influenza A (H1N1) Virus Infection
supplemental interviews for all patients with reported cases
starting in 2003, supplemental interview data were not avail- — Mexico, March–April 2009
able for all reported cases. Interviewed patients might have On April 30, this report was posted as an MMWR Dispatch
represented those who were easier to contact, and the analysis on the MMWR website (http://www.cdc.gov/mmwr).
might have underrepresented persons with certain risk fac- In March and early April 2009, Mexico experienced out-
tors, such as drug use. Finally, responses to interviews might breaks of respiratory illness and increased reports of patients
be subject to recall and information bias given the sensitive with influenza-like illness (ILI) in several areas of the country.
nature of some questions (e.g., regarding the number of sex On April 12, the General Directorate of Epidemiology (DGE)
partners and drug use). reported an outbreak of ILI in a small community in the state
With the epidemic now growing in different populations and of Veracruz to the Pan American Health Organization (PAHO)
requiring different prevention approaches, adequate contain- in accordance with International Health Regulations. On April
ment will be a challenge. Public health officials should include 17, a case of atypical pneumonia in Oaxaca State prompted
data on sex of partners with case reporting, as recommended enhanced surveillance throughout Mexico. On April 23,
by CDC (1). STD programs should employ methods that several cases of severe respiratory illness laboratory confirmed
have been successful in the past, including serologic screening as swine-origin influenza A (H1N1) virus (S-OIV) infection
in high-prevalence populations such as in corrections settings, were communicated to the PAHO. Sequence analysis revealed
facilitating access to effective treatment, and accessing and that the patients were infected with the same S-OIV strain
treating partners, particularly those most likely to sustain detected in two children residing in California (1). This report
transmission (8). describes the initial and ongoing investigation of the S-OIV
outbreak in Mexico.
The findings in this report are based, in part, on contributions by Enhanced Surveillance
S Yu, MPH, Jefferson County Dept of Health.
On April 17, in response to the increase in reports of
References respiratory illness, DGE issued a national epidemiologic alert
1. CDC. The National Plan to Eliminate Syphilis from the United States,
2006. Atlanta, GA: US Departmen