Treatment of Swine flu Influenza

Antiviral Treatment:

• Should be considered for confirmed, probable, or suspected cases of swine flu virus infection.
• Oseltamivir and zanamivir should be initiated as soon as possible after the onset of symptoms.
• Recommended duration of treatment is five days.
• Doses recommended for treatment are the same as those recommended for seasonal influenza.
• Oseltamivir use in children <1 year old was recently approved by the FDA under an Emergency Use Authorization (EUA).
  

Antiviral Chemoprophylaxis:

• Chemoprophylaxis is recommended for:
  • Household close contacts who are at high-risk for complications of influenza (eg, certain medical conditions, persons ≥65 years old, children <5>
  • School children who are at high-risk for complications of influenza and who had close contact with a confirmed, probable, or suspected case.
  • Travelers to Mexico who are at high-risk for complications of influenza.
  • Healthcare workers and public health workers who were not using appropriate protective equipment during close contact with an ill confirmed, probable, or suspected case during the infectious period.
• Chemoprophylaxis (pre-exposure) may be considered for:
  • Healthcare workers at high-risk for complications of influenza and who are working in areas that contain patients with confirmed illness or who are caring for patients with acute febrile respiratory illness.
  • Non-high risk persons who are travelers to Mexico, first responders, or border workers who are in areas with confirmed cases.
• Oseltamivir or zanamivir may be used.
• Post-exposure: duration of chemoprophylaxis is 10 days after last known exposure to ill confirmed case.
• Pre-exposure: chemoprophylaxis should be given during potential exposure period and for 10 days after last known exposure.
• Oseltamivir may be used for chemoprophylaxis in children <1>

level of swine influenza pandemic alert raised from phase 3 to phase 4

Human cases of swine influenza A/H1N1 virus infection also have been confirmed internationally: US has reported 40, Canada has reported 6 confirmed human cases of infection; Spain has reported 1 case; Scotland has reported 2 cases. Mexico has reported 26 cases of infection, including 7 deaths.

On the advice of the Emergency Committee of the World Health Organization, the Director-General has raised the level of influenza pandemic alert from phase 3 to phase 4. The change to a higher phase of pandemic alert indicates that the likelihood of a pandemic has increased, but not that a pandemic is inevitable.

The Emergency Committee's recommendation is based on the available data on confirmed outbreaks of A/H1N1 swine influenza in the United States, Mexico, and Canada. The Committee also considered reports of possible spread to additional countries.

The decision was based primarily on epidemiological data demonstrating human-to-human transmission and the ability of the virus to cause community-level outbreaks.

Given the widespread presence of the virus, the Director-General considered that containment of the outbreak is not feasible. The current focus should be on mitigation measures.

In Mexico, the suspected number of cases is reportedly as high as 1,600, and the suspected number of deaths in Mexico is up to 80. Potential new cases also have been reported in France, Hong Kong, and New Zealand. These numbers and reports are not yet confirmed.

Laboratory testing has found the swine influenza A/H1N1 virus is susceptible to the prescription antiviral drugs oseltamivir and zanamivir.

New subtype of influenza virus - Swine influenza

The Centers for Disease Control and Prevention (CDC) report laboratory-confirmed human cases of swine influenza A/H1N1. Human cases of swine influenza A/H1N1 virus infection also have been identified internationally.

Based on preliminary testing, the virus is being described as a new subtype of A/H1N1 not previously detected in swine or humans.

Laboratory testing has found the swine influenza A/H1N1 virus is susceptible to the prescription antiviral drugs oseltamivir and zanamivir. According to Anne Schuchat, MD, the CDC's Interim Deputy Director for Science and Public Health Program, treatment should begin within 48 hours of onset. Vaccine development is in process, but it will take several months to prepare a vaccine.

CDC has issued interim recommendations for diagnostic testing and antiviral use, but local and state circumstances may vary and individual protocols may be put in place.

The CDC also has prepared interim guidance on how to care for people who are sick and interim guidance on the use of face masks in a community setting where spread of this swine flu virus has been detected. This is a rapidly evolving situation and CDC will provide new information as it becomes available.

The World Health Organization (WHO) reports that the government of Mexico also has reported several laboratory-confirmed cases of swine influenza A/H1N1. In a media briefing today, the CDC confirmed several swine influenza-related deaths as well. Investigation is continuing to clarify the spread and severity of the disease in Mexico. Suspect clinical cases have been reported in 19 of the country's 32 states.

Investigations are ongoing to determine the source of the infection and whether additional people have been infected with swine influenza viruses.

CDC is working very closely with officials in states where human cases of swine influenza A/H1N1 have been identified, as well as with health officials in Mexico, Canada, and WHO. This includes deploying staff domestically and internationally to provide guidance and technical support. CDC has activated its Emergency Operations Center to coordinate this investigation.

WHO and the Global Alert and Response Network (GOARN) are sending experts to Mexico to work with health authorities. WHO and its partners are actively investigating reports of suspect cases in other Member States as they occur and are supporting field epidemiology activities, laboratory diagnosis and clinical management.