Sexually transmitted disease

Sexually transmitted disease

  • Various STDs are caused by bacteria viruses and protozoa.
  • Most STDs is are curable or at least can be controlled by antibiotics.
  • long-term health consequences of STDs are serious.
  • As an example some STDs can cause secondary health problems like pelvic inflammatory disease heart and nerve damage.


  • Extremely sensitive to environmental condition.
  • Killed very fast by drying, sunlight and UV light.
  • Cause eye infection in newborn and adult.
  • Transmitted by intimate host-to-host contact.
  • Symptoms of gonorrhoea are different in male and female.
  • In the female, a mild infection in the genital region and is difficult to distinguish from other infection.
  • In the male, it causes a painful infection of the urethral canal.
  • Treatment with penicillin has been successful.

(2) Syphilis:-

  • These are more serious disease than gonorrhoea.
  • Caused by spirochaete.
  • The organism cannot pass through normal skin so initial infection is through a small break on skin.
  • The genital organ of male and female gets infected.
  • Pathogen transmits from infected women to fittest.
  • This kind of disease is known as congenital syphilis.


  • Caused by Herpes viruses.
  • Cause fever blister, cold sore.
  • There are two types of herpes viruses:-
  • HV1- cause cold sore and fever blister around the mouth and lips.
  • HV2- infection at anogenital reasons cause a painful blister on the genital organ of male and female.

(4) trichomoniasis:-

  • Non-gonococcal urethritis can also be caused by protozoa and trichomonas vaginalis.
  • They can survive outside the host if do not dry.


  • Acquired immunodeficiency syndrome caused by the human immunodeficiency virus is a retrovirus.
  • Which enters the host cell genome.
  • Effect of HIV on the immune system leads to AIDS.

▶Animal transmitted disease:-animal Transmitted disease spread accidentally to host through direct contact aerosols or bites.


  • Rabies is a very serious disease.
  • Infected to human from animals.
  • Caused by rhabdo virus family.
  • Infected cells of central nervous system.
  • Virus present in saliva rabied animals and enters the host body by bite wound.
  • The incubation period is 10 to 14 days in dog.
  • symptoms:-Virus proliferate in the brain causing fever , anxiety , a fear of swelling and ultimately result in respiratory paralysis.

(2) hantavirus pulmonary syndrome:-

  • Caused by hantavirus a member of burya viridae family.
  • Single stranded RNA viruses.
  • Cause hantavirus pulmonary syndrome with renal syndrome.
  • Contaminated by rodents like mice, rat etc.
  • Humans get infected by inhalation of virus contaminated rodents.
  • There is no virus specific vaccines.
  • Can be prevented by avoiding contact with rodent and its habitat.

▶Insect and ticks transmitted disease:-


  • Caused by rickettsia Shia a small bacteria grow intracellular by
  • Spread by blood sucking anthropoids.
  • Typhus fever :- Rickettsia prowazekii.
  • transmitted from human to human by body or head.
  • Rickettsia comes from contaminated faeces of louse.
  • The incubation period in human wants 2-3 weeks.
  • Symptoms are fever headache, body weakness, rashes in armpits and then to other parts only accept facepalm and sole of feet.
  • No treatment may cause damage to the central nervous system lungs, kidney, heart.

(2) spotted fever:-

  • Transmitted by ticks. (Dog ticks and wood ticks).
  • Contaminated faecal matter of tax injected to organism body by bite, rubbing or stretching.
  • Incubation period 3- 12 days inside the host cell nucleus as well as cytoplasm.
  • Symptoms are fever several headaches, rash on palm and sole, a gastrointestinal problem like diarrhoea vomiting.
  • Tetracycline, chloramphenicol antibiotics are effective.

Other Rickettsial diseases:-

  • Fever is a pneumonia-like infection caused by Coxiella Brunetti.
  • Transmitted to animal by insect bite and from animal to man.

▶Lime disease

(1)Tick-borne diseases

  • Affect animal and human.
  • Caused by spirochaete.
  • Symptoms are effects central nervous system, visual disturbance, facial paralysis miscarriage and stillbirth.
  • Treatment can be done by tetracycline and penicillin.

(2) malaria:-

  • Caused by protozoa Plasmodium vivax.
  • Transmitted by female mosquitoes of gonas anopheles.
  • Present at the salivary gland of insect.
  • symptoms are vomiting, severe headache cycle, anaemia due to loss of RBC.
  • Treatment of effective chloroquine and primaquine together.

(3) plague:-

  • Caused by bacteria.
  • Yersinia pestis grand negative, facultative, aerobic rod.
  • Domestic and wild rodents are disease reservoir.
  • Human is an accidental host.
  • Symptoms are lymph node pain, blackening of skin death within 3 to 5 days.
  • Treatment is as effective with alternate use of streptomycin and tetracycline