Leprosy- Epidemolgy,Vaccination,NTLEP

Ans. is ‘a’ i.e., Skin to skin contact; ‘c’ i.e., Droplet spread 

Ans. is ‘c’ i.e., Rifampicin, ofloxacin and minocyclin single dose 

For patients with single – lesion paucibacillary leprosy, the who recommends as an alternative a single dose of rifampicin, ofloxacin and minocycline.

C. i.e. Early diagnosis & treatment

Ans. is ‘a’ i.e., Uterus 

Leprosy

o Leprosy (Hansen’s disease) is a chronic infectious disease caused by M. leprae.

o It effects mainly the peripheral nerves, but may also affect skin, muscle, eyes, bones, testes and internal organs (Liver, spleen, kidney).

o Leprosy is clinically characterised by one or more of the following cardinal features :‑

a)  Hypopigmented patches

b)  Partial or total loss of cutaneous sensation

c)  Presence of thickened nerves

d)  Presence of acid-fast bacilli in the skin or nasal smear.

About option a & b

The female genital tract is rarely involved in leprosy, when involved ovary is the most common gynaecological site to be involved.

Ans. is ‘a’ i.e., Prevalence decreasing in past decade 

o Over the years, prevalence increased from 8.4 cases per, 10,000 population in 1966 to a peak of 12 per 10,000 in 1985. o Since then there has been a steady decline, and at the beginning of 2008, the number of leprosy cases in the world

was around 212, 802 and global prevalence rate of leprosy was below 1 per 10,000 population.

Epidemiological determinants of leprosy

o Agent –> M. leprae

o Source of infection —> Multibacillary cases (most important), subclinical infections. The role of individuals with tuberculoid forms of the disease sources of infection is not clear. The current view is that all patients with active leprosy must be considered infectious.

o Infectivity —> Leprosy is a highly infectious (communicable) disease with low pathogenicity. An infectious patient can be rendered non-infectious by treatment with dapsone for about 90 days, or with rifampicin for 3 weeks. Local application of rifampicin (drop or spray) might destroy all the bacilli within 8 days.

o Age —> Peak incidence between 10-20 years.

Ans. is ‘d’ i.e., Insect can transmit the disease

o “Leprosy is not particularly a disease of children as was once believed. However, the presence of leprosy in child population is of considerable epidemiological importance. A high prevalence of infection among children means that the disease is active & spreading” – Park 20th 278.

o Lepra bacilli can survive for long periods of time in soil under favourable environmental condition. There is now evidence that natural infection with M. leprae are present in wild animals e.g. armadillos, managabey monkeys & chimpanzees.

o The tuberculoid type of lesions are bacteriologically negative. The role of individuals with tuberculoid forms of the disease as sources of infection is not yet clear.

“Bacterial load is highest in lepromatous cases whereas tuberculoid type is bacteriologically negative”.

o “Bacilli may also be transmitted by insect vectors or by tattoing needles. However, there is no evidence that any of these transmission route is important in nature” – Park 20th 279

o “Relapse rate is one of the best indicators of the efficacy of the drug regimen” – Park 20th 288

Ans. is ‘b’ i.e., Long contact with tuberculoid leprosy can transmit the disease 

o Multibacillary cases (Lepromatous and broderline lepromatous) are the most important sources of infection in the community. The role of individuals with tuberculoid forms of the disease as a source of infection is not clear and if these cases possess only a limited capacity to infect others they may be important because a relatively large number of this form of leprosy occurs in endemic communities. The current view is that all patients with “active leprosy” must be considered infectious.

o The infectivity of patients with paucibacillary (tuberculoid) leprosy is much lower. – Greenwood 16th/e p. 213. From above statements it is clear that the risk of transmission in a case of tuberculoid leprosy is small but still they can transmit the disease.

About other options

Option ‘a’

o Lepra bacilli can not be cultivated invitro.

Option ‘c’

o Cell mediated immunity is deficient in lepromatous leprosy.

Option ‘d’

“The first sign of leprosy is a non specific or determinate skin lesion, which often heal spontenously. If the

disease progresses, its clinical manifestation is determined by specific immune responsiveness of the patient to

the bacillus and there is distinct immunological spectrum (from T.T. to L.L.)” – Greenwood 16^th/e p. 210

From above statement it seems that skin lesions often heal spontenously before tuberculoid leprosy i.e., in indeterminate form.

Macular lesion is seen in tuberculoid leprosy, so it will not regress spontaneously.

Ans. is ‘a’ i.e. BCG, ‘c’ i.e. ICRC bacillus

Leprosy Vaccine (1mmunoprophylaxisl

o In view of the variable protective effect of BCG vaccine against leprosy, several alternative vaccine preparations are under development. These should be appropriately called “candidate vaccines”.

o All the reported “candidate” vaccines have shown a similar degree of lepromin conversions in lepromatous patients (50-70 %) and lepromin negative healthy individuals (90 %)

()Maximum work has been done with BCG + heat killed M. leprae. However, none of the candidate have attained as yet “vaccinehood”.

Ans. is ‘a’ i.e., Early detection of cases; ‘b’ i.e., Short course multi drug therapy; ‘c’ i.e., Rehabilitation

Piational I.eprosv Eradication Programme (INTLEP)

National leprosy Control Programme was launched in 1955 by Government of India. as a centrally aided programe to achieve control of leprosy through early detection of cases and dapsone monotherapy on an ambulatory basis.

o In 1983 the control programme was redesignated National Leprosy Eradication Programme with the goal of eradicating the disease by the turn of the century.

• The aim was to reduce case load to I or less than 1 per 10000 population.
• Revised strategy (NLEP) was based on

i)   Early detection of case

ii)  Short term multi-drug therapy

iii)        Health education

iv)       Ulcer and deformity care

v)   Rehabilitation activities

o NLEP provided : ‑

i)  Domiciliary treatment in endemic districts through specially trained staff.

ii) In moderate to low endemic districts, services through mobile leprosy treatment units and primary health care persons.

Ans. is ‘a’ i.e. Increasing number of children affected’ 

FNaluation of programme:

here are two main types of indicators in leprosy control

a)       Operational indicators

These are related to case-finding, treatment, relapses & disabilities for e.g.

o Relapse rate – One of the best indicators of the efficacy of drug regimen

o Case detection ratio – No. of cases registered / no. of cases estimated.

o Proportion of children among newly detected cases.

o Proportion of multibacillary cases on regular treatment during the year.

o Proportion of female cases among newly detected cases.

o Treatment completion/cure rate.

o Proportion of new cases presenting with grade 2 disability/impairment at the time of diagnosis. o Proportion of treatment defaulters.

o Proportion of patients who develop new/additional disability during MDT.

b)       Epidemiological indicators:

To assess the impact of the actions taken with regard to the problem reduction.

o Incidence rate – most sensitive index of transmission of disease. Only index for measuring the effectiveness of the measure taken i.e. reduction of transmission.

o Prevalence – This provides a measure of case load & is useful in planning of the treatment services.

High new case detection rate comes under operational indicators which shows that the Leprosy Control Programme is effective in detecting new cases from the already pool of leprosy cases. Thus these new cases could be treated to reduce further transmission of disease.

Ans. is ‘b’ i.e., 1-5

Ans. is `b’ i.e., Early diagnosis and treatment 

• Early diagnosis & Treatment is the most important part of NLEP.

Note:

Other diseaes for which early diagnosis & treatment is the most important step in control  TB, STD.

Ans. is ‘d’ i.e., 1983

Ans. is ‘b’ i.e., Ovary 

Ans. A: Uterus

Main organs/ tissue involved in leprosy are skin and peripheral nerves Systemic (eyes, testes and reticuloendothelial system) involvement is common

Leprosy:

• Hansens disease
• Virchow cells are seen
• CNS, ovaries, lungs are NOT commonly involved in leprosy
• TT is the MC type of leprosy in India
• Tuberculoid leprosy:

– Infective form

Ulnar nerve is a commonly affected nerve

– Followed by posterior auricular nerve

Lepromatous leprosy:

– Presents with gyanecomastia, madrosis, collapse of nasal bridge

– Histologically, the dermis characteristically contains highly vacuolated cells (foam cells) and fewer or absent non-caseating granuloma 1^st line drug:

– Rifampicin

– Dapsone

– Clofazimine

DOC in neuritis: Steroids

Nerve abscess treated by: Incision and drainage

Lepra reaction type 1:

– Corticosteroids are the DOC

– Unresponsive to thalidomide Lepra reaction type II:

– Also known as erythema nodosum leprosum

– Seen in lepromatous leprosy

– Thalidomide is effective Lepromin test indicates strong immunity

Ans. is ‘a’ i.e., Incidence 

Incidence rate

• It is the only index for measuring the effectiveness of the measures taken. 
• It is the most sensitive index of transmission of the disease.
• Prevalence
• It provides a measure of the ‘case-load’.
• It is useful in the planning of treatment services.
• The efficacy of the drug regimen is best indicated by relapse rate.