Standard Operating Procedures for
Surveillance and Rapid Response
For Human Cases of
Avian Influenza Disease (Bird Flu)
Developed with joint collaboration of
the Public Health Laboratories Division, National Institute of Health,
Islamabad
February 2006
Table of Contents
Equipping
Public Health Officers on Rapid Response Teams
Duties
of Public Health Officers on Rapid Response Teams
2.
Sentinel Site Surveillance teams
3.
Checklist for hospitalization of human cases of AI
4.
Investigating Clusters of Human cases.
Annex 1. Personal Protection
Equipment (PPE)
Annex
2: Collection of clinical specimens from
the respiratory tract
Annex
5: SOPs for Virology Lab Handling of Specimens for Avian Influenza
Annex
6: Checklist for Hospital Preparedness for Human Cases of AI
Rationale
After isolation of H5N1 type of bird flu in poultry of
Objectives
The objectives of human influenza surveillance are:
To identify human Avian Influenza H5N1 virus infections
To appropriately treat the cases
To appropriately isolate the cases and reduce chance of transmission
To monitor close contacts for early diagnosis and treatment
To evaluate the effect of the preventive measures in the current risk groups
To identify new risk groups that need to be targeted by preventive measures.
Planned actions
1- To designate and train two public health officers to participate with Ministry of Food, Agriculture and Livestock (MINFAL)/ Provincial Department of Food, Agriculture and Livestock in each of the Rapid Response Teams (RRT) to investigate possible human cases of Avian Influenza.
2- To start surveillance for human cases of AI at tertiary hospitals and collect samples from patients hospitalized with serious pneumonia within three days of onset of illness, if possible.
3- To provide a checklist to assist provincial health departments to assure preparedness for hospitalization and case management of human cases of AI.
1. Rapid Response Teams
Rapid Response Teams (RRT) are being constituted by the Ministry of Food, Agriculture and Livestock (MINFAL)/ Provincial Department of Food, Agriculture and Livestock to investigate suspected outbreaks of Avian Influenza (AI) in poultry or migratory birds. 4 to 6teams of four members in each province have been trained and supplied with provided personal protective equipment (PPE), disinfectant solutions and sprayers for initial steps in control of an outbreak among poultry.
Two public health experts would be identified and trained to respond to suspected outbreaks of Avian Influenza in poultry or migratory birds. When notified of a suspected outbreak of AI, the RRT would visit the affected area and the public health officers would conduct surveillance for human cases of AI among high risk population such as poultry handlers or villagers living near a body of water where migratory birds have been affected by AI.
Equipping Public Health Officers on Rapid Response Teams
Public health officers on Rapid Response Teams would be provided with personal protective equipment including gloves, masks, goggles, gowns, caps and boots and would be trained in their use. See Annex 1.
They would also be provided with viral transport media and swabs and cold boxes and ice packs for collection and transport of specimens (Annex 2) and investigation forms (Annex 3).
Duties of Public Health Officers on Rapid Response Teams
Public health officers on RRT will screen poultry handlers, farmers, their families or other potentially exposed persons to identify patients to be sampled for viral isolation according to definition for Influenza-Like Illness (ILI) below:
Person with acute respiratory illness, characterized by fever (temperature greater than 38.5 degrees C) AND cough, sore throat, or shortness of breath OR child with signs of serious illness indicated by respiratory rate:
≥60 breaths/minute in a child aged <2 months;
≥50 breaths/minute in a child aged 2–12 months;
≥40 breaths/minute in a child aged 12 months to 5 years
The officer will ensure that the patient meets the case definition and the onset of illness is recent, within three days if possible. The officer will explain the procedure and get the verbal consent from the patient or parent (in the case of a child) and will record patient’s name/ father’s name, complete address, age, sex, patient history and details about the contact with poultry birds/ migratory birds, hospital status and local lab results on the investigation form (Annex 3).
The officer will obtain a respiratory specimen on nasopharyngeal swab and place in Viral Transport Media bottle and package for transport (Annex 2) to Virology Lab at Public Health Laboratories Division of National Institute of Health.
Patients will be advised for treatment or referred to the hospital according to the flow chart in Annex 4.
2. Sentinel Site Surveillance teams
Sentinel site surveillance would initially be the responsibility of Polio (PEI) Team. The designated surveillance officer would visit major tertiary hospitals on a weekly basis and collect samples of possible cases of Avian Influenza or if notified of a probable Avian Influenza case. See definitions in box.
Surveillance officers would be provided with personal protective equipment including gloves, masks, goggles, gowns, caps and boots and would be trained in their use. See Annex 1. They would also be provided with viral transport media and swabs and cold boxes and ice packs for collection and transport of specimens (Annex 2) and investigation forms (Annex 3).
The surveillance officer will ensure that the patient meets the case definition and the onset of illness is recent. The officer will explain the procedure and get the verbal consent from the patient or parent (in the case of a child) and will record patient’s name/ father’s name, complete address, age, sex, patient history and details about the contact with poultry birds/ migratory birds, hospital status and local lab results on the investigation form (Annex 3).
Specimen collection
The surveillance officer will obtain a respiratory specimen on nasopharyngeal swab and place in Viral Transport Media bottle and package for transport (Annex 2) to Virology Lab at Public Health Laboratories Division of National Institute of Health.
If there is a probable case of Avian Influenza, in addition to obtaining respiratory specimen, the surveillance officer will obtain serum from the patient. An acute-phase serum specimen (3–5 ml of whole blood) should be taken soon after onset of clinical symptoms and not later than 7 days after onset. A convalescent-phase serum specimen should be collected 14 days after the onset of symptoms. Where patients are near death, a second ante-mortem specimen should be collected. Although single serum specimens may not provide conclusive evidence in support of an individual diagnosis, when taken more than 2 weeks after the onset of symptoms they can be useful for detecting antibodies against avian influenza viruses in a neutralization test.
Specimen transport
Specimens for transport must be surrounded by
absorbable material such as cotton, placed in leak-proof specimen bag, and
sealed in another bag or container to further isolate and prevent
breakage. Specimens must be kept at 4°C with icepacks inside a
cold box and transported to the laboratory within 2 days. Repeated freezing and
thawing must be avoided to prevent loss of infectivity. Icepacks and cold boxes
can be provided by the Polio Program focal point.
Investigation forms should be also kept in the cold box with the specimen so they are not misplaced. When samples have been collected, the officer would call the specified courier and hand over a cold box lined with four fresh ice packs and containing the specimens along with the investigation form for each specimen.
Personnel who transport specimens should be trained in safe handling
practices and decontamination procedures in case of a spill. A register should be kept of all those who
have handled specimens of patients being investigated for influenza.
Specimen processing
The Virology Department at National Institute of Health has the capabilities to carry out:
• Isolation of influenza viruses in tissue cell culture or by egg inoculation
• Sero-typing of influenza viruses
• Immuno-fluorescence assay
• Enzyme Linked Immuno-Sorbant Assay (ELISA)
• Polymerase Chain Reaction (PCR)
See Annex 5 for SOPs for handling specimens by Virology Lab.
3. Checklist for hospitalization
of human cases of AI
A draft checklist to assist provincial health departments to assure preparedness for hospitalization and case management of human cases of AI is provided in Annex 6.
4. Investigating Clusters of Human cases.
Beyond the investigation of individual cases of human –avian influenza, the responsibility to investigate clusters of cases would fall with the Epidemic investigation Cells in each province or district.
Investigation of case clusters is critically important because careful questioning result in unique and important insights about how the cases are epidemiologically linked and how the people are getting infected by H5N1 virus. The following recommendations are general recommendations for investigating clusters. Since clusters are often unique, individual investigations should be tailored according to the situation.
- All activities (including travel) conducted by each H5N1-infected person in a cluster during the week before illness started should be identified, explored in detail and documented in a written report. It is particularly important to be open minded about potentially new ways in which people may be exposed to H5N1.
- Investigators should try to identify any links between the ill persons, for example, common activities or exposures
- If any common links are found, additional questioning or investigations should be pursued as indicated.
2. Since H5N1 might be transmitted from animals to people or person to person, some questions should specifically should probe for identifying the following exposures if possible, for example
a. Contact with another person infected by H5N1
b. Contact with a person with a febrile or respiratory illness
c. Contact with poultry or wild birds infected by H5N1
d. Contact with objects or surfaces potentially contaminated by bird feces
e. Contact with poultry infected by H5N1
f. Contact with pigs
When possible, investigators also should visit and inspect any locations where infection may be occurring to assess the plausibility of that infection could have occurred in that place.
Annex 1. Personal Protection Equipment (PPE)
Annex 2: Collection of clinical specimens from the respiratory
tract
Background
Diagnostic tests available for influenza include viral culture, serology,
rapid antigen testing, polymerase chain reaction (PCR), and immunofluorescence
assays. Among respiratory specimens for viral isolation or rapid detection,
nasopharyngeal specimens are typically more effective than throat swab
specimens. As with any diagnostic test, results should be evaluated in the
context of other clinical and epidemiologic information available to
health-care providers.
Despite the availability of rapid diagnostic tests, collecting clinical
specimens for viral culture are critical, because only culture isolates can
provide specific information regarding circulating strains and subtypes of
influenza viruses which is needed to guide decisions regarding influenza
treatment and chemoprophylaxis, to monitor the emergence of antiviral
resistance and the emergence of novel influenza A subtypes that might pose a
pandemic threat, and to formulate a vaccine.
Samples should be collected within the first 4 days of illness. Rapid
influenza tests provide results within 24 hours; viral culture provides results
in 3-10 days. Most of the rapid tests are approximately 70% sensitive for
detecting influenza and approximately 90% specific. Thus, as many as 30% of
samples that would be positive for influenza by viral culture may give a
negative rapid test result, and some rapid test results may indicate influenza
when a person is not infected with influenza.
|
Procedure |
Influenza Types Detected |
Acceptable Specimens |
Time for Results |
|
Viral culture |
A
and B |
NP swab, throat swab, nasal wash, bronchial wash,
nasal aspirate, sputum |
5-10 |
|
Immunofluorescence
DFA Antibody Staining
|
A
and B |
NP swab, nasal wash, bronchial wash, nasal
aspirate, sputum |
2-4
hours |
|
RT-PCR |
A
and B |
NP swab, throat swab, nasal wash, bronchial wash,
nasal aspirate, sputum |
1-2
days |
|
Serology
* |
A
and B |
Paired acute and convalescent serum samples 6
|
>2
weeks |
|
Enzyme
Immuno Assay |
A
and B |
NP swab, throat swab, nasal wash, bronchial wash |
2
hours |
NP = nasopharyngeal
* A fourfold or
greater rise in antibody titer from the acute- (collected within the 1st week
of illness) to the convalescent-phase (collected 2-4 weeks after the acute
sample) sample is indicative of recent infection.
Moderately complex
test – requires specific laboratory certification.
Collection of clinical specimens from the upper
respiratory tract
All specimens should
be regarded as potentially infectious and staff who take, collect or transport
clinical specimens should adhere rigorously to protective measures in order to
minimize exposure. Minimum protection
for the staff taking the specimen would be mask and gloves, while others
handling the specimen should wear gloves at least.
Nasopharyngeal
swabs
Use only
sterile polyester swabs with plastic or wire shafts. Do not use calcium
alginate swabs or swabs with wooden sticks, as they may contain substances that
inactivate some viruses and inhibit PCR testing.
To obtain a nasopharyngeal
swab, insert a swab into the nostril parallel to the palate. Leave the swab
in place for a few seconds to absorb secretions. Withdraw the swab with a
rotating motion. Obtain specimen
from the other nostril with the same swab.
Place the swab
immediately into sterile vials containing 2 ml of viral transport media (VTM).
Break the applicator sticks or cut the wire near the tip to permit tightening
of the cap. Label each specimen container with the patient’s ID number and the
date the sample was collected.
The accompanying request form should be clearly labelled with the
following information: name, age, gender of patient, telephone contact, date of
collection, date of onset of illness, village, and name of the health facility.
Storage and
transportation of clinical specimens
Standard
precautions should always be followed, and barrier protection applied whenever
samples are obtained from patients, i.e. wear gloves when handling specimens.
Specimens for transport must be surrounded by absorbable material such
as cotton, placed in leak-proof specimen bag, and sealed in another bag or
container to further isolate and prevent breakage.
Specimens must
be kept at 4°C with icepacks inside a cold box and transported to the
laboratory within 2 days. Repeated freezing and thawing must be avoided to
prevent loss of infectivity. Icepacks and cold boxes can be provided by the
Polio Program focal point.
Personnel who transport specimens should be trained in safe handling
practices and decontamination procedures in case of a spill. A register should be kept of all those who
have handled specimens of patients being investigated for influenza.
Annex 3: Investigation Form
Annex 4: Flow chart for triage of patients
with acute respiratory illness during investigation of Avian Influenza
