Veterinary Epidemiology and Zoonosis

NOTIFIABLE DISEASES : SOURCE OF INFECTION AND PREVENTION

Reference: http://www.tnhealth.org/ 

AIDS

• Caused by a virus called Human Immuno Deficiency virus.
• There are about 13 million cases by 1999 Worldwide and 6.7 million in South and South East Asia.
• It is transmitted from person to person through sexual contact, sharing of virus contaminated needles and syringes, transfusion of infected blood.
• Transmission at the contact with saliva, tears, urine not occurred.

Prevention

• Have sexual intercourse with wife/husband only.
• Abstain from sexual intercourse with unknown persons.
• Use condoms during sexual acts.
• Use of sterilized needles / syringes, disposable needles.
• Screening of blood and blood products.
• Care in handling, using and disposing of blood and blood products, needles and sharp instruments.
• Disinfection of equipment contaminated.

CHICKEN POX

• It is an acute viral disease, with slight fever, malaise and a skin eruption.
• It is caused by a virus Herpes virus 3.
• Transmitted from person to person by direct contact by droplet or by air borne spread.

Prevention

• Report to local health authorities.
• Exclude children from school, emergency rooms (or) public places until the vesicles become dry.
• Articles contaminated should be disinfected.
• Vaccine is recommended for susceptible persons following exposure to virus.
• Vaccine may be given to the children aged 12 to 18 months and for the children up to 12 years who have not had varicella.
• The vaccine has efficacy of 70-90%.

CHOLERA

• Caused by a bacteria Vibrio cholerae.
• Affected person will have sudden onset of profuse painless watery stools, nausea, vomitting.
• If not treated in early stages, rapid dehydration, collapse and renal failure will occur.
• Transmitted by ingestion of food or water contaminated directly or indirectly.

Prevention

• Report to local health authority.
• Hospitalization of severe patients.
• Mild cases can be treated at house by use of oral rehydration solution.
• Treatment consists of rehydration therapy and administration of antibiotics.
• Treatment of complications.
• Disinfection of feces, vomitting and of linens, articles used by the patient.
• Vaccination is of little practical value in outbreaks.

DENGUE FEVER

•  Caused by virus flavivirus.
• There will be sudden onset, fever for 3-5 days severe headache, muscle pain, joint pain, pain in the eyes, digestive problems.
• In haemorrhagic disease, there will be bleeding nose, gum, hypovolemia and abnormal blood clotting properties.
• Transmitted by a mosquito Aedes aegypti.

Prevention

• Eliminating mosquito by net, protective clothing, repellants and avoiding stagnation of water.
• Treatment is only supportive.
• Aspirin should not be used because it may cause bleeding in the stomach.
• The haemorrhagic cases have to be hospitalised.

DIPTHERIA

• Caused by bacteria corny bacterium Diptheriae.
• It involves tonsils, pharynx, larynx, nose, skin, conjunctiva or vagina.
• There will be asymmetrical grayish, whitish membrane, nasal discharge.
• Transmitted by contact with a patient or carrier.

Prevention

• Report to local health authority.
• Effective way of control is immunisation with diptheria toxoid.
• At present it is given as DPT in 45 days, 75 days, 105 days of age and at 18 months as booster and as DT in 5 years of age in India.
• Disinfection of articles soiled by discharge of patient.

HEPATITIS

Hepatitis A

• Start with fever malaise, anorexia, nausea and abdominal discomfort, followed by jaundice.
• Caused by Hepatitis A virus.
• Transmitted from person to person by the fecal - oral route.
• Common source outbreaks related to contaminated water and food, infected food handlers.

Prevention

• Education about good sanitation and personal hygiene.
• Proper water treatment.
• Vaccines are available for 2 years of age and older.

Hepatitis B

• Caused by hepatits B virus.
• Start with nausea, vomitting, abdominal discomfort, joint pain and jaundice.
• Transmitted by blood and blood produce sexual contacts, infected saliva and other body sections.

Prevention 

• Effective vaccines are available.
• Screening of blood products.
• Adherence to sterilization procedures.

INFLUENZA

• Caused by influenza viruses.
• Characterized by fever, headache, muscle pain, running nose, sore throat and cough.
• Transmitted by airborne among crowded population.

Prevention

• · Education about basic personal hygiene, especially danger of unprotected cough and sneezes.
• · Vaccination may provide 70-80% protection.

LEPROSY

• Caused by a bacteria called Mycobacterium leprae.
• It is the bacterial disease that affects skin and peripheral nerves and the upper airway.
• It will be presented as hypopigmented patches, thickened nerves and deformities.

Prevention 

• Early detection of cases with white and shining patches without any sense.
• Prompt treatment with multidrug.
• Health education.
• Environmental sanitation.

MEASLES

•  Caused by measles virus.
• Presented as fever, conjunctivitis, cold, cough and small spots with bluish white centers and red base on the buccal mucosa.
• Transmitted by direct contact or airborne.

Prevention 

• Active vaccination with measles vaccine after completion of 9 months of age among children.
• Children affected should be kept out of schools and in isolation.

CEREBRO SPINAL FEVER

• Caused by a bacteria, Neisseria meningititis.
• Occurs as sudden onset of fever, intense headache, nausea, vomitting, stiff neck, rash and coma.
• Transmitted by direct contact, respiratory droplets.

Prevention

• Report to local health authorities.
• Education on the need to reduce direct contact and droplet infection.
• Reduce overcrowding.
• Close surveillance of household, day care.
• Vaccines are available.

WHOOPING COUGH ( Pertusis )

• Caused by the bacteria bacillus (Pertusis)
• Occurs as initiating cough which becomes repeated violent cough followed by high pitched respiratory whoop.
• It occurs among children.
• Transmitted by direct contact with discharges.

Prevention

• Report to local health authority.
• Active immunization which is now given along with diptheria and tetanus as DPT.
• Isolation of cases.
•  Quaranting from schools for 21 days.
• Education of public.

PLAGUE

• Caused by the bacteriae Yersinia pestis.
• Occurs as fever, chills, tiredness, muscle pain, nausea, sore throat and headache.
• Enlargement of lymph nodes also occur.
• Transmitted by the bite of infected fleas.

Prevention 

• Report to local Health Authorities.
• Reduction of flea source, control of rates.
• Personal protection.
• Isolation of cases.
• Quarantine for 7 days.

POLIO

• Caused by Polio virus types 1, 2, 3.
• Occurs as fever, malaise, headache, nausea, vomitting, muscle pain, stiffness of the back and neck with FLACCID PARALYSIS.
• Transmitted from person to person by fecal-oral route.

Prevention

• Report to the local Health Authority.
• Active immunization with Polio vaccines. It is given as oral polio drops. It should be given at birth, 45 days, 75 days, 105 days and 9 months of age and at 1 1/2 years.
• In view of eradicating polio, 2 rounds Pulse Polio is given since from 1995. The child should also receive this pulse polio in addition to the routine Immunisation.
• Personal and environment hygiene.

RABIES

• Caused by virus Rabies virus.
• Followed by a bite or scratch of a rabies affected animal.
• Occurs as headache, fever, tiredness, indefinite sensory changes
• The main features are excitability, aerophobia (fearness to the speed air), difficulty in swallowing, hydrophobia (fear of water).
• Without treatment death occurs due to respiratory paralysis.

Prevention 

• Register license and vaccinate all dogs.
• Treat the wound immediately by thorough cleaning. The wound should not be sutured.
• Effective vaccination is available for the both exposed and non-exposed persons.

SMALL POX

• Caused by Variola virus.
• Occurs as sudden fever, malaise, headache, prostration, severe back ache, abdominal pain and vomitting.
• A deep-seated rash developed with face and extremities.
• Transmitted from person to person.
• In Biowar it would most likely be disseminated in an aerosol cloud.

Prevention

• Report to local Health Authority.
•  Vaccine is available.
• This disease was eradicated globally in 8th May, 1980.

TETANUS

• Caused by bacteria Clostridium tetani.
• Occurs as painful muscular contraction, first affecting the cheek and neck muscles and then trunk muscles.
• A common first sign in older children and adult is abdominal rigidity.
• Transmitted by wound contaminated with soil, feces.
• It occurs in new borne which is called as neonatal tetanus if safety methods are not followed during delivery.

Prevention 

• Immunization with tetanus toxoid.
• Pregnant Women: 2 doses of tetanus toxoid. At 16-20 weeks and 24 weeks of pregnancy. To prevent neonatal tetanus.
• For Infants: Included in DPT and to be given at 45 days, 75 days, 105 days and 1 1/2 years of birth. DT at fifth year. TT at 10^th year and once in five years. Thorough cleaning of the wound. Avoid frequent TT injection, whenever get injured.

TUBERCULOSIS

• Caused by bacteria Mycobacterium tuberculosis.
• It affects lungs, mainly intestine, brain, bones and joints lymph glanes.
• Occurs as cough more than 3 weeks, fever, loss of weight, loss of appetite.
• Transmitted as airborne droplet.

Prevention 

• Education about the importance of early diagnosis and prompt treatment.
• Improvement in housing venitlation.
• Environmental sanitation.
• BCG Vaccine at the time of birth.
• To combat the tuberculosis now, revised National Tuberculosis Control Programme is being implemented in Govt.PHCs / Hospitals which ensures the successful treatment.

VIRAL ENCEPHALITIS

• Caused by many viruses.
• Occurs as sudden fever, severe headache, vomitting, stiffness of neck.
• Transmitted person to person, direct contact.

Prevention

• Report to local Health Authority.
• Environment and personal hygiene.
• Food and water sanitation.
• Prompt treatment.