Highly infectious diseases transmitted by direct contact or contact with infected materials, clothing, discharges, vomit, etc. are cholera, rabies, tetanus, anthrax, poliomyelitis, mumps, septicaemia, typhoid, tuberculosis, hepatitis B & C, diphtheria, C.S.F. meningitis, smallpox, plague, tick- borne encephalitis, equine encephalomyelitis, Tcell lymphotropic viruses I and II, and HIV.
Patients with presenile dementia may have Creutzfeldt-Jakob disease (CJD) caused by virus, which is present in highest concentration in nervous and lymphoid tissues. It appears that the CJD agent can be acquired only by ingestion, inoculation or transplantation. Hepatitis B and C viruses are present in blood stream and concentrated in hepatic tissue.
Inoculation tuberculosis of skin (prosector’s wart) is rarely seen in persons engaged in postmortem examinations. There is a risk of transmission of HIV through needle prick injury during collection of blood and other body fluids, and mucosal splashes and skin contact with superficial injury during autopsy on a HIV infected dead body.
HIV in high concentrations has been found to remain viable for three weeks and from liquid blood after two months. HIV and hepatitis viruses are not associated with airborne transmission. HIV is present mostly in lymphoid tissue and brain, and also in colon and lungs.
It is better to leave some organs in situ in the cadaver rather than eviscerating en masse. Another method is to fix lungs and other organs whole after removal rather than slicing them before fixation.
Universal Work Precautions:
(1) All infected bodies should be wrapped and tied in double layer tough plastic bag, with a red colour tag mentioning “Biologically Hazardous’. The label should mention the name, age, sex, registration number, etc.
(2) Workers who have exudative lesions or weeping dermatitis or external injury should not handle AIDS victims.
(3) Proper protective clothing, full sleeves overalls instead of simple surgical gowns, water-proof plastic apron, head cap, face mask, goggles if eye glasses are not worn, double gloves (heavy autopsy gloves over surgical gloves), waterproof rubber gumboots of knee length with shoe covers. A plastic visor will protect eyes and mucosal surfaces from splash injury. A high efficiency particulate air-filled respirator or a powered air-purifying respirator should be worn.
(4) Handling sharp instruments: Avoid accidental pricks and cuts from needles, scalpels, etc. If a cut is made in the rubber gloves or needle injury occurs they should be removed immediately and replaced with new ones. Hands and other skin surfaces should be washed immediately and thoroughly if contaminated with blood or other body fluids. Infection of AIDS can be acquired by transdermal inoculation through cuts and needle punctures. About 0.5% of individuals will become seropositive. Transmission rates from contaminated needle punctures or close contact are 10 to 30 times higher for serum hepatitis than for AIDS. The incident should be reported to proper authority to get their blood check for HIV seropositivity.
(5) Handling specimens for laboratory examination: Mucocutaneous contact with the body fluids, and aerosol inhalation should be avoided. They should be properly labelled and filled with 10% formalin solution and should be handled with gloved hands.
(6) Disposal of used instrumeits: They should be dipped in 20% glutaraldehyde (cidox) for half-an-hour, washed with soap or detergent and water, dried and then rinsed in methylated spirit and air dried.
(7) All soiled gauze and cotton, etc. should be collected in a double plastic bag for incineration.
(8) Laundry material, such as aprons, towels, etc. should be soaked in one percent bleach for half-an-hour, washed with detergent and hot water, and autoclaved.
(9) Clean-up procedure: Wear new intact disposable gloves. Small spatters and spills of blood and other body fluids can be wiped up with disposable tissues or towels which are discarded in special bio-hazard bags and properly disposed. The autopsy table and floor should be cleaned with one percent bleach solution, followed by washing with soap and water.
(10) Disinfectants: 1:10 dilution of common household bleach or a freshly prepared sodium hypochlorite solution is recommended. Liquid chemical germicides commonly used in health care facilities and laboratories are effective against HIV.
(11) In case of accidental injuries or cuts with sharp instruments, contaminated with blood or body fluids or not, while working on a body, the wound should be immediately washed thoroughly under running water, bleeding encouraged and disinfected.
(12) To minimise aerosol splatter, skull can be opened with an electrical oscillting saw attached to a vacuum dust exhaust and filter or with a band saw under a transparent anti-slash cover. After autopsy all body orifices should be packed and the body should be wrapped in double layer heavy plastic sheet bag and secured properly, so that there is no leakage. A tag should be attached for identification.
(13) After completing autopsy, hands and face should be washed with soap and water and rinsed in 70% methylated spirit.
(14) The body should be burnt or incinerated.
Universal precautions apply to blood, semen and vaginal secretions as well as to CSF, synovial fluid, pleural fluid, peritoneal fluid, pericardial fluid and amniotic fluid. Universal precautions do not apply to faeces, nasal secretions, sputum, sweat, tears, urine and vomitus unless they contain visible blood. If the recommended guidelines are adhered to, there is no risk to the staff conducting autopsies on AIDS patients.
THE AUTOPSY AND DISPOSAL OF RADIOACTIVE CORPSE
If the amount of radioactivity is less than 5 millicuries, no extra precautions are necessary. If the body contains between 5 to 30 millicuries of radioactive material, the doctor must wear heavy rubber gloves, plastic aprons, plastic shoe covers and spectacles to reduce contamination. Instruments with long handles should be used during the autopsy.
Organs and fluids that are most radioactive should be removed first and placed in covered glass jars, labelled and examined for radioactivity from time to time. Fluid of the pleural and peritoneal cavity should be flushed copiously with running water and disposed off directly into the sewer.
Contaminated wearing dress should be thoroughly cleaned with soap and water, and stored for suitable decay of the radioactive material before being sent to laundry. Instruments can be brought to a safe level by soaking them in water with soap or a detergent.
Contamination of the floor of the autopsy room should be avoided. Spilled fluid should be cleaned with dry disposable water, held with forceps and put into a suitable vessel. If the radiation level is high, a team may be required to complete the autopsy. Special organs may be removed first, and detailed dissection done away from the body, or after a period of cold storage, or fixation to permit radioactive decay.
If the body contains more than 300 millicuries of activity after autopsy, it should be embalmed in the hospital morgue. The presence of a cardiac pace-maker must be recorded, especially if it is one which might contain mercury or a radioactive substance, as explosions in crematoria from the heating of mercury batteries have proved hazardous.