Yellow Fever

Question 1

Mention at least 10 zoonotic diseases

Answer 1

Yellow fever
Leishmania
Schistosomiasis - bilharzia
Hydatid disease - echinococcosis
Rabies - hydrophobia
Plague - black death
Malaria
Brucellosis - Malta fever
Anthrax - wool sorter’s disease
Toxoplasmosis
Leptospirosis
Rickettsia disease - spotted fever

Question 2

What is Yellow fever?

Answer 2

arboviral disease of monkey transmitted to men

Question 3

What is the meaning of arbovirus

Answer 3

Arthopod
Born
Virus
(Virus infection from arthropods)

Question 4

The endemic zone of yellow fever

Answer 4

In africa bt 15 °N & 10 °S of equator

Question 5

Yellow fever in libya

Answer 5

Not seen, but however requires immediate notification

Question 6

magnitude of disease problem of yellow fever

Answer 6

In Africa and south America.

Question 7

Agent of yellow fever

Answer 7

Flavivirus fabricus is a virus of arbovirus group B (S.S RNA)

Question 8

Reservoir of yellow fever infection

Answer 8

In the forest area : monkey d luffy (just kidding)
In urban or rural area: the men

Question 9

Vector

Answer 9

Aedes egypti and Aedes africanus mosquitoes

Question 10

Host factors:

Answer 10

All ages & both sexes are susceptible
Occupation : Hunters, wood cutters whose occupation brings them in contact with forests are at risk of infection
Urbanization : In Africa, urbanization is leading to extension of Yellow fever.
Immunity:
• One attack of Y. fever gives life long immunity.
• Infants born of immune mothers have antibodies up to 6 months of life

Question 11

Environmental factors :

Answer 11

• Temperature of >24 C is required for multiplication of the virus in mosquito
⁃ Humidity of > 60% for the mosquito to live

Question 12

Mode of Transmission : 2 ways

Answer 12

Jungle y. fever (sylvatic cycle): vector for it is aedes africanus. The cycle of transmission is monkey- Mosquito- man.
Urban/rural Y. fever: vector is Aedes aegypti. The cycle of transmission is **Man-Mosquito- man(*

Question 13

Period of communicability & Incubation period

Answer 13

Period of communicability = Blood of man is infective to mosquitoes during 3-4 days of illness, Once the mosquito becomes infective (10 days after an infective blood meal), it remains infective for the rest of natural life.
Incubation period : 3-6 days

Question 14

Diagnosis

Answer 14

• Preliminary diagnosis: the patient’s clinical features, places and dates of travel, and activities.
• Laboratory diagnosis: IgM and IgG antibodies by serologic assays
• Diagnostic tests: Indirect fluorescent antibody test, ELISA, and PCR

Question 15

Treatment of y.fever

Answer 15

There is no specific anti-viral treatment for yellow fever, only supportive care to treat symptoms like fever and dehydration.

Question 16

Vaccination:

Answer 16

• 17D, a freeze- dried live attenuated vaccine.
• It is given S/C at the insertion of deltoid in a single dose of 0.5 ml.
• No given to children under one year of age.
• Immunity begins to appear on the day 7th and lasts for > 35 years.
• W.H.O recommends revaccination after 10 years for international travel.

Question 17

In Libya

Answer 17

• Libya is a Yellow fever “Receptive area”
• The population of Libya is unvaccinated and susceptible to Y. fever.
• The vector is present
  * The virus does not exist.
• It is an exotic disease for Libya