The California Department of Public Health (CDPH) is dedicated to protecting the health and well-being of the people in California. Due to the recent activity of novel avian influenza A (H7N9) in China, CDPH is distributing information to heighten surveillance and infection control to prevent the spread of this novel virus.
On April 1, 2013, the World Health Organization (WHO) reported the first known human infections with a novel avian influenza A (H7N9) virus in China. As of April 23, 2013 a total of 108 human cases of avian influenza A (H7N9) virus infection have been reported, including 22 deaths. In addition, one asymptomatic case has been identified. On April 23, 2013 the Taiwan Centers for Disease Control (CDC) reported the first human case of avian influenza A (H7N9) in a Taiwanese citizen with documented travel to China. This is the first case of avian influenza A (H7N9) detected outside of mainland China.
Most cases have been identified in the provinces of Jiangsu (23), Shanghai (34) and Zhejiang (42), all of which are on the east coast of China. A smaller number of cases have been identified in the provinces of Anhui (4), Henan (3), Beijing (1) and Shandong (1). As indicated above, one case has been reported in Taiwan. New cases continue to be reported and case counts are likely to increase. Updates are available at:
World Health Organization - Disease Outbreak News
While investigations are ongoing, there is currently no evidence that the virus has become easily transmissible from person-to-person. CDPH will continue to monitor the situation in China closely and will provide updates as new information becomes available. For now, all healthcare providers should be on alert to identify any patients with influenza-like illness* (ILI) symptoms.
Who should be considered a suspect case of avian influenza A (H7N9)?
A patient with influenza-like illness* (ILI) meeting either of the following exposure criteria:
- Recent travel (within ≤ 10 days of illness onset) to China; OR
- Recent contact (within ≤ 10 days of illness onset) with a confirmed or probable case of infection with novel influenza A (H7N9) virus.
*ILI is defined as fever (temperature of 100°F [37.8°C] or greater) and cough and/or sore throat.
Cases under investigation with severe respiratory illness (including radiographically-confirmed pneumonia, acute respiratory distress syndrome (ARDS), or other severe respiratory illness) of unknown etiology may be prioritized for diagnostic testing.
Infection control precautions for suspect, probable or confirmed H7N9 cases
CDC has issued interim guidance for influenza A (H7N9) infection control precautions, which are available at: CDC - Interim Guidance for Infection Control Within Health Care Settings. The guidance includes the recommendation that healthcare personnel providing care for patients with confirmed or probable avian A (H7N9) infection, or cases under investigation use Standard Precautions plus Contact and Airborne Precautions, including eye protection and the expanded use of respirators for all patient-care activities until more is known about the transmission characteristics of the influenza A (H7N9) virus. Aerosol-generating procedures should be performed on such patients only if they are medically necessary and cannot be postponed.
These recommendations are more stringent than the infection control precautions used routinely for seasonal influenza because there is currently:
- No H7N9 vaccine
- A suspected high rate of morbidity and mortality among infected patients
- An unknown potential for person-to-person transmission
- An absence of confirmed or probable H7N9 cases in the United States
Many primary care clinics will not be able to implement all elements of airborne precautions, i.e., placing patient in airborne infection isolation room. However, all possible precautions should be taken to minimize the risk of exposure to staff and patients, including the following:
- Receptionists and phone triage personnel should ask all patients with ILI if they have had travel to China within 10 days of symptom onset.
- Patients with ILI and a history of travel to China should be seen at the end of the day or when fewer people are in the clinic, if possible.
- Such patients should be given a surgical mask to wear upon entering the clinic and should be immediately placed in a room with a door that closes, and not remain in waiting areas.
Testing for avian influenza A (H7N9)
Clinicians should obtain a nasopharyngeal swab or aspirate, place the swab or aspirate in viral transport medium, and contact their local health department to arrange transport of the specimen for testing. Specimens should be collected using appropriate infection control precautions. For additional guidance on diagnostic testing of patients under investigation for novel influenza A (H7N9) virus infection, please see guidance for avian influenza A(H5N1) testing, which is also applicable to H7N9, at:
CDC - Interim Guidance for Speciment Collection, Processing, and Testing for Patients with Suspected Infection
Treatment for suspect, probable or confirmed avian influenza A (H7N9) patients
The CDC has issued interim guidance on antiviral treatment of human infections with avian influenza A (H7N9), which is available at: CDC - Interim Guidance on the Use of Antiviral Medications for Treatment of Human Infections. Because of the potential severity of illness associated with this infection, CDC recommends that all confirmed, probable, and cases under investigation, including outpatients with uncomplicated illness, be treated with neuraminidase inhibitors as early as possible. Clinicians should not wait for laboratory confirmation of influenza before initiating treatment.
Reporting suspect cases
Clinicians should notify their local health department immediately of any suspect novel influenza cases, including H7N9. Specimens from patients with suspected avian influenza A (H7N9) virus infection should be submitted for testing regardless of on-site rapid influenza testing results.
Thank you for your help in our influenza surveillance efforts around avian influenza A (H7N9). Please share this information with your healthcare providers.
If you have any questions regarding the infection prevention and control of this novel influenza virus, please contact the CDPH Healthcare Associated Infections (HAI) Program - Rebecca Siiteri (firstname.lastname@example.org) or Dr. Kavita K. Trivedi (Kavita.email@example.com).
Original Signed By Debby Rogers
Debby Rogers, RN, MS, FAEN