ICMR releases SOP for diagnosing and managing anthrax

Mumbai, June 1, 2022:

The Indian Council of Medical Research (ICMR), the country’s apex body for promotion of biomedical research, has come out with standard operating procedure (SOP) for anthrax. The SOP will be of tremendous use as a national guideline for handling suspected human, animal and environmental specimens towards diagnosing and managing anthrax.

It will also add fillip to the existing biosafety measures in the country and facilitate responsible handling of agents of biothreat potential.

Anthrax is a serious infectious disease caused by gram-positive, rod-shaped bacteria known as Bacillus anthracis. It occurs naturally in soil and commonly affects domestic and wild animals around the world. People can get sick with anthrax if they come in contact with infected animals or contaminated animal products. Symptoms depend on the route of infection. They can range from a skin ulcer with a dark scab to difficulty breathing. Antibiotic treatment cures most infections. Inhaled anthrax is harder to treat and can be fatal.

The SOP was developed by ICMR along with Christian Medical College (CMC), Vellore and Centre for Arboviral and Zoonotic diseases, the National Centre for Disease Control (NCDC) under the Union ministry of health and family welfare.

Anthrax is a lethal bacterial disease with additional potential of Bacillus anthracis being used as a bioweapon. It is also important to recognize that persistent hot spots of anthrax with repeated outbreaks have been reported in the past from different parts of India. Effective control of anthrax depends on timely diagnosis and reporting, which presently remains as major lacunae in several endemic regions of the country. This resource material has been developed as a reference manual to respond to such observations and to guide laboratories on standardized uniform protocols for diagnosis.

“Anthrax is a neglected disease with a potential for natural or manmade outbreaks. Anthrax remains a remarkably under-reported disease due to failure to suspect, detect and diagnose the disease in many parts of India. The extraordinary stability of Bacillus anthracis spores that survive in soil for around 200 years and their resistance to many of the disinfection procedures demands extremely careful handling of samples or bacterial cultures and following stringent decontamination procedures. The ICMR has been at the forefront of addressing public health challenges and in providing technical support to fill the aforementioned gaps in biomedical research. This SOP is a step towards such endeavour. It is a practical manual intended to be used as a reference guide by various laboratories in different parts of the country. The manual describes the safe and scientific methods of specimen collection, transport, culture, identification and molecular testing for diagnosing Anthrax,” said Prof (Dr) Balram Bhargava, Director General, ICMR and Secretary, Department of Health Research.

The SOP called for providing training to laboratory personnel in biosafety and biosecurity measures before commencing work as well as ensuring their adherence to safety protocols.

“All laboratory procedures should be performed in the Biosafety Level 3 containment facility (BSL III) inside Biosafety cabinet Class III to minimize production of potential aerosols. General Good Laboratory Practices (GLP) must be followed as per the World Health Organization (WHO) guideline for Anthrax, 4th edition 2008. Laboratory personnel should wear a gown or laboratory coat with long sleeves and elastic cuffings and disposable gloves. Appropriate disinfectant (usually 10% hypochlorite solution) should be prepared freshly on a regular basis. Screw capped non-breakable containers should be used for transport of specimens, cultures, etc. Autoclavable carriers or secondary containers should be used for moving cultures within the laboratory,” stated the national guidance document for anthrax.

The SOP has strictly prohibited storage of samples and B.anthracis isolates in the laboratory. “Samples and isolates should be kept only till the results are reported. After reporting, the samples and isolates should be autoclaved and decontaminated as per protocol of the World Health Organization (WHO). Isolates may be sent to the reference laboratory for confirmations (National reference laboratory, Department of Clinical Microbiology, Christian Medical College, Vellore (CMC), Tamil Nadu and Centre for Arboviral and Zoonotic Diseases (CAZD), National Centre for Disease Control (NCDC), New Delhi),” it added.

Besides this, SOP also stressed for autoclaving of laboratory accessories like pipettes, tips, loops, spreaders etc or fully immersing the equipment in 10% hypochlorite or formalin to make them disinfectant. It further said all materials used including labware should be decontaminated by autoclaving at 121 C for 30 minutes to 1 hour preferably followed by incineration. Microscopic slides, cover slips and other sharp items should be placed in autoclavable sharp containers and autoclaved, preferably followed by incineration. Infectious disposable waste should be autoclaved followed by incineration.

If accidental spillage or exposure to anthrax spores occurs in the laboratory (including spills of infectious substances like blood or body fluids), PPE should be worn before cleaning the spillage (Gloves, protecting clothing including face and eye shield), it stated.

All cultures of Bacillus anthracis, specimens and disposable labware used for isolation, identification and performing molecular characterization should be decontaminated by placing in double autoclave bags for autoclaving followed by incineration, it pointed out.

Talking about the process for disposal of Anthrax carcasses, the SOP prohibited use of lime or other calcium products on carcasses or contaminated ground. Carcasses disposal should be done by incineration. However, deep burial is also an acceptable method. Performing an autopsy is prohibited when anthrax is being considered, it enumerated.

Talking about specimen transport, it said all specimens are collected in appropriate leak proof containers and secured, the sample container is put in a clear plastic cover with biohazard label, sealed and immediately transported to the laboratory (hand carried) and handed over to the lab staff.

Shedding light on processing of sample, it stated that the sample is processed in the biosafety cabinet BSLIII type 2B2. Smears are prepared and cultures inoculated here, including the culture follow-up.

The SOP guidance document also specified various parameters to diagnose anthrax. Rapid initiation of appropriate antibiotic therapy is crucial in the treatment of anthrax particularly in the systemic manifestations. Penicillin has been the drug of choice for all types of anthrax since the 1940s, but naturally occurring strains are increasingly reported to be resistant. B. anthracis is sensitive to a broad range of antibiotics including tetracyclines, macrolides, aminoglycosides, and first, second, third-generation cephalosporins etc, said the SOP guideline.

The gold standard for determining antimicrobial susceptibility for Anthrax is the conventional broth microdilution (BMD) method which is based on the Clinical and Laboratory Standards Institute guidelines, it said. PharmaBiz