The document discusses different types of ectoparasite infestations including tungiasis (jiggers), fleas, lice, and their prevention and treatment. It provides details on the clinical features and life cycles of each parasite. For all infestations, prevention focuses on hygiene, environmental controls like cleaning living areas, and application of insecticides. Treatment involves carefully removing parasites from the skin followed by cleaning and medicating the affected area.

1. Ectoparasites Infestation

2. Learning Objectives
By the end of this session, students will be able to:
● Explain overview of different ecto-parasites infestation
● Explain clinical features and treatment of jiggers, flea, lice infestation
● Explain prevention and control measures of jiggers, flea, lice infestation

3. TUNGIASIS
•: A disease caused by flea called Tunga penetrans (Jiggers).
• It is not contagious, so it is not transmitted from one person to person but it is
always through external environment.
• Jiggers are common in some rural locations and transmission is by penetration to
skin.
• Both male and female jigger fleas are blood suckers of all warm blooded animals.
• The male leaves its host after obtaining the meal, but the female, when pregnant,
burrow into soft skin commonly between the toes where they lay eggs.
• The hind part of flea protrudes through the skin so the egg can be released.
• In children, other parts of the body e.g. buttocks can also be infested by the flea.

4. Clinical Features and Treatment
• After penetration and burrowing into the skin, the result is a small, round itching,
painful swelling with point (hind part of the flea).
• Secondary bacterial infection is common and occasionally tetanus may result.
• Treatment is by mechanical removal of the flea by sterile pin followed by antiseptics
dressing.
• Avoid application of kerosene because this will kill the flea but results in ulceration
of skin until the dead flea is expelled.

5. Prevention and Control Measures
• Jiggers are more common in rural areas as many people walk bear footed.
• Wearing shoes provide protection.
• Keeping house and environment clean will reduce contact between human and
fleas.
• Pyrethrum as a spray or as a powder will kill jigger fleas.

8. Flea infestation
• Flea: The common name for insects of the order Siphonaptera which are wingless insects with
mouthparts adapted for piercing skin and sucking blood.
• Fleas are external parasites.
• Pulex irritans is the human flea.
• Pulicosis (also known as ‘flea bites’): A skin condition caused by several species of fleas.
• Besides the problems posed by the creature itself, fleas can also act as a vector for disease.
• Fleas transmit not only a variety of viral, bacterial and rickettsial diseases to man and other
animals but also protozoans and helminths.
• The most common disease transmitted by fleas is bubonic plague.
• Fleas transmit the disease between rodents and humans by carrying Yersinia pestis bacteria.

10. Clinical Features and Treatment of Flea Infestation
• Fleas are nuisance to their hosts, causing an itching sensation which in turn may result in
scratching.
• Some people suffer allergic reactions to flea saliva resulting in rashes (dermatitis).
• Flea bites generally result in the formation of a slightly-raised swollen itching spot with a single
puncture point at the center (similar to a mosquito sting).
• The bites often appear in clusters or lines of two bites, and can remain itchy and inflamed for up
to several weeks afterwards.
• Fleas can also lead to hair loss as a result of frequent scratching
• Hypersensitivity reactions to fleas can cause severe dermatitis, especially in children
• When scratching, one can move the flea faeces into the open wound, spreading bacteria or
diseased organisms into the body.

11. Treatments
• The itching associated with flea bites can be treated with anti-itch creams,
usually with antihistamine or hydrocortisone these reduces itching.
• Calamine lotion has been shown to be effective for itching.
• Wash the bites with antiseptic lotion or soap.
• Use cool water, as hot water may stimulate itching.
• Make sure tetanus vaccine is up to date (vaccinate for those who need it).
• After several days post exposures if patient present with fever, or enlarged
lymph nodes, has to be investigated in order to exclude infection like plague.

12. Prevention and Control Measures of Flea
● Rid the area of the fleas to prevent further bites.
● Treat pets for fleas using repellant powder
● Pyrethrum as a spray or as a powder will kill fleas
● Environment hygiene control should eliminate fleas and eliminate an
infestation

13. Pediculosis
Pediculosis: An infestation of lice blood-feeding ectoparasitic insects of
the order Phthiraptera.
• The condition can occur in almost any species of warm-blooded animal
including humans.
• Although ‘pediculosis’ in humans may properly refer to lice infestation of
any part of the body, the term is sometimes used loosely to refer to
pediculosis capitis, the infestation of the human head with the specific
head louse.

14. Classification
Pediculosis may be divided into the following types:
• Pediculosis capitis
o Head-louse infestation is most frequent on children aged 3–10 and their families.
o Head lice are spread through direct head-to-head contact with an infested person.
o From each egg or ‘nit’ may hatch one nymph that will grow and develop to the adult louse.
o Lice feed on blood once or more often each day by piercing the skin with their tiny needle-
like mouthparts.
o While feeding they excrete saliva, which irritates the skin and causes itching.
o Lice cannot burrow into the skin.

16. • Pediculosis corporis
o This condition is caused by body louse (Pediculus humanus humanus, sometimes
called Pediculus humanus corporis is a louse which infests humans and is adapted to
lay eggs in clothing, rather than at the base of hairs.
o This type of Pediculosis is a more serious threat due to possible contagion of
diseases such as typhus and louse borne relapsing fever (Borrellia recurrentis).
o Body lice are spread through prolonged direct physical contact with a person who
has body lice or through contact with articles such as clothing, beds, bed linens, or
towels that have been in contact with an infested person.

17. Pediculosis pubis (Crabs)
o Humans are the only known host of this parasite.
o The pubic or crab lice (Pthirus pubis) are parasitic insects notorious for infesting human genitals.
o The species may also live on other areas with hair, including the eyelashes. o They feed exclusively
on blood.
o Pubic lice usually infect a new host only by close contact between individuals, usually through sexual
intercourse.
o Parent-to-child infestations are more likely to occur through routes of shared towels, clothing, beds or
closets.
o Adults are more frequently infested than children.
o As with most sexually transmitted pathogens, they can only survive a short time away from the
warmth and humidity of the human body.

18. Clinical Features and Treatment of Pediculosis
• The most characteristic symptom of infestation is pruritus (itching).
• Lice cause irritating bites, which form papules.
• This results in scratching which may be followed by secondary infection.
• Nits can be seen on shafts of hair.
• Excessive scratching of the infested areas can cause sores, which may become
infected.

19. Prevention and Control of Pediculosis
• Shaving off or grooming any hair in the affected areas with a fine-toothed comb is
necessary to ensure full removal of the dead lice and nits.
• Delousing can also be practically achieved by boiling all clothes and bed clothes.
• Temperature of 130 °F (55 °C) for 5 minutes will kill most of the adults and prevent
eggs from hatching.
• Where this is not practical or possible, powder dusting with 10%
dichlorodiphenyltrichloroethane (DDT), 1% Malathion or 1% permethrin is also
effective (DDT and malathion should not be used on the body or ingested)
• If insecticide is not available, louse-infested clothes and bedding can be burned on
an open fire