LEVELS OF PREVENTION

1.Prevention of the emergence/development of the riskfactors, in the population, in which they have not appeared yet: Primordial prevention

2.Action taken prior to onset of disease, which lessens the possibility of occurrence of the disease (health promotion & specific protection-immunization, chemoprophylaxis): Primary prevention

3.Action halting the progress of disease at early stage & preventing its complication (includes early diagnosis & treatment): Secondary prevention

4.Disability limitation & Rehabilitation: Tertiary prevention

INDICES

Physical Quality of Life Index/ PQLI - Morris D. Morris developed  PQLI. hree indicators like life expectancy, infant mortality rate and literacy rate.

CASE CONTROL STUDY/ RETROSPECTIVE STUDY

A retrospective study looks backwards and examines exposures to suspected risk or protection factors in relation to an outcome that is established at the start of the study .

Suitable for rare diseases.

COHORT STUDY/ PROSPECTIVE STUDY

STERILIZATION & DISINFECTION

sterilisation - refers to any process that eliminates, removes, kills, or deactivates all forms of life and other biological agents (such as fungi, bacteria, viruses, spore forms, prions, unicellular eukaryotic organisms such as Plasmodium, etc.) present in a specified region, such as a surface .

Disinfectant kills all pathogenic micro-organisms

Bacteriostatic agent - A bacteriostatic agent or bacteriostat, is a biological or chemical agent that stops bacteria from reproducing, while not necessarily killing them otherwise .

Most resistant to sterilization: Prions 

Disposable syringes are sterilized by: Gamma rays 

Vaccines are sterilized by: Heat inactivation

Cold sterilization is done by: Gamma rays 

Reidel walker coefficient: Determines germicidal efficiency of disinfectants .

Vaccines are sterilized by: Heat inactivation.

BIOLOGICAL TRANSMISSION

Propagative - When the disease agent or parasite undergoes multiplication within the body of biological vector but no cyclical change is observed, then the transmission is said to be propagative.

ex -Plague bacilli in rat flea

Cyclo-propagative - Here the parasite undergoes multiplication in the body of the vector and at the same time cyclical change is also noticed.

ex -Malaria parasite in mosquito

Cyclodevelopmental - When the disease agent or parasite undergoes no multiplication in the body of vector but they undergo cyclical changes

ex- Microfilaria in mosquito

IMMUNIZATION

Ring immunization: - controls an outbreak by vaccinating and monitoring a ring of people around each infected individual. The idea is to form a buffer of immune individuals to prevent the spread of the disease.Given around 100 yards of a case detected.

Live vaccines: - Live vaccines use a weakened (or attenuated) form of the germ that causes a disease. Because these vaccines are so similar to the natural infection that they help prevent, they create a strong and long-lasting immune response. exBCG, Yellow fever (17D) .

Killed vaccine - To produce this type of vaccines, bacteria or viruses are killed or inactivated by a chemical treatment or heat. This group includes for example the inactivated poliovirus (IPV) vaccine, pertussis vaccine, rabies vaccine, or hepatitis A virus vaccine. 

Fragment vaccine - Hepatitis B 

Freeze dried vaccine - Lyophilized (freeze-dried) vaccines For optimal potency, freeze-dried vaccines . WHO no longer recommends that freeze- dried vaccines 

Strain used in BCG - Danish 1331

Strain used in OPV -  Sabin strain

Strain used in Chicken pox-  Oka strain

There is NO vaccine for Dengue fever yet

Influenza vaccine is administered as -  Nose drops

HPV vaccine is - Both bivalent & quadravalent

MEASLES

Measles is an infectious disease caused by the rubeola virus. 

Special feature: Kopliks spot

Incubation period: 10-14 days

Rash appears on: 4th day

Contamination of measles vaccine can cause: TSS (toxic shock syndrome)

RUBELLA

also known as German measles or three-day measles .

infection caused by the rubella virus .

Risk to fetus is maximum if mother gets infected during: 6-12 weeks of pregnancy

Congenital rubella syndrome: Deafness, Cardiac malformations, Cataracts

Rubella vaccine is given: To girls, between 11-14 years of age .

RABIES

Rabies is a viral disease that spreads through the bite of an infected animal.

Symptoms include fever, headaches, and weakness.

Symptoms appear in: About 10 days (4 days - 8 weeks) 

Immunofluorescence is used for diagnosing Rabies

Vaccine recommended by WHO: HDC vaccine

YELLOW FEVER

symptoms include fever, chills, loss of appetite, nausea, muscle pains particularly in the back, and headaches.

Caused by -  Flavivirus

POLIO

also known as poliomyelitis is a highly contagious disease caused by a virus that attacks the nervous system .

Cause of death in polio -Respiratory paralysis

Pulse polio was introduced in India in -  1995

Pulse polio is given to children below - 5 years

A country is said to be polio FREE if there is no case confirmed for last - 5 years

MALARIA

Malaria is a life-threatening mosquito-borne blood disease caused by a Plasmodium parasite .

Once an infected mosquito bites a human, the parasites multiply in the host's liver before infecting and destroying red blood cells 

Symptoms are chills, fever and sweating, usually occurring a few weeks after being bitten.

The severity of malaria varies based on the species of plasmodium. 

Dengue is caused by: Aedes

Infective agent of malaria is: Sporozoite

Not seen in peripheral blood smear of falciparum: Schizont

Size of RBC is increased in: Vivax malaria 

Most virulent species of malaria - P.falciparum

Exo-erythrocytic stage is absent - P.falciparum 

TB

Mycobacterium TB was.discovered by - Robert Koch

Acid fastness is due to - Mycolic acid & cell wall

Tuberculin test-Prevalence of TB in community is assessed by

Ghon focus is related to - Primary pulmonary TB

LEPROSY

also known as Hansen's disease 

Leprosy is caused by infection with the bacterium Mycobacterium leprae. 

Symptoms include light-coloured or red skin patches with reduced sensation, numbness and weakness in hands and feet. 

"Hansen's disease" is named after the Norwegian physician Gerhard Armauer Hansen. 

Generation time of lepra bacilii - 12 days

Lepra bacilli can be grown in -  Foot pad of mice

Spreads by - Skin to skin contact

Lepra cells are - Histiocytes

RICKETTSIAL DISEASE

Brill Zinser disease is- is a delayed relapse of epidemic typhus, caused by Rickettsia prowazekii. 

Vector for Epidemic typhus -Louse

Vector for Endemic typhus - Rat flea

Vector for Scrub typhus - Mite

OBESITY

Indices for obesity:
-BMI (Quetlet's index),
-Corpulence index

BMI - is a measure of body fat based on height and weight that applies to adult men and women .

is calculated as: Weight/ height 2 

Abdominal fat accumulation is assessed by: Waist/ hip ratio

WATER

Recommended level of fluoride in drinking water is-0.5-0.8 mg/ litre

Recommended fluorine concentration in water - 1.5 ppm

Hardness level of water which requires softening - 3-6 (150-300)

Ortho-toluidine test - Determines both free & combined chlorine

Horrock's apparatus - Measures chlorine demand of water

VITAMIN

Bleeding disease is due to the deficiency of - Vitamin K 

Vitamin D deficiency is the reason for - Rickets 

Earliest sign of vitamin A deficiency -  Conjunctivalxerosis

Vitamin which prevents lipid peroxidation - Vitamin E 

Enlargement of thyroid gland is due to the deficiency of  - Iodine 

Cyanocobalamine deficiency is the reason of  - Pernicious anaemia 

Vitamin which is required for gamma carboxylation - Vitamin K

The condition of inflammation and cracking of skin at corners of mouth is - Cheilosis

Calcium deposition in soft tissues is due to  - excess of vitamin D 

Beriberi is due to the deficiency of  - vitamin B1

PNEUMOCONIOSIS

An occupational lung disease and a restrictive lung disease caused by the inhalation of dust, often in mines and from agriculture .

Bagassosis -  Inhalation of sugar cane dust .

Farmers lung is caused by - Micropolyspora faeni

Monday fever is associated with -  Byssinosis

Byssinosis, also called "brown lung disease" or "Monday fever"

Snow storm appearance is seen in - Silicosis.

WASTE MANAGEMENT

DEMOGRAPHIC CYCLE

A nation’s population passes through 5 phases during it’s development -

first stage High stationary

• Birth rate and death rates are high and cancel each other
• Population size remains stationary

• The death rate starts declining
• Birth rate remains high
• Birth rates may even increase due to improved health conditions and decreased period of breast feeding

Third stage-late expanding - Death rate decline still further and the birth rate tends to fall, population
continues to grow as births exceed deaths.

Fourth stage-low stationary: This stage is characterized by low birth and low death rate the population
becomes stationary .

Fifth stage Declining-

• The birth rate falls below death rate
• The population size starts falling