Symptoms of an ill traveller. Diagnosing the tropical traveller

In every ill traveller is necessary to consider the symptoms thatt may reveal a tropical disease:

Malaria
It presents with fever,rigors,headache,dizzines,flulike symtopms,diarrhea.
Mosquitos may stowaway in luggage causing malaria in non -tropical areas.
Typhoid
It presents with fever,relative bradicardia (low heart rate),abdominal pain,dry cough,constipation,lymphodenophaty (lymph nodes abnormal in size),headache and rarely rose spots.
Dengue fever
Its presents with fever,headache,myalgia,skin rush,pallor.
Amoebic liver abscess
Presents with fever,jaudince,upper abdomen pain.

Travelling to a tropical area does not mean that having fever or headche symptoms are signs of a tropical disease,that's why is necessary to have a doctor visit a the necessary investigations in establishing the exact diagnosis in time,prevent catching a tropical disease by vaccination before travveling and avoid as much as possible contact with contaminated food and water.

You can get infected by eating raw,improperly cooked fish or freshly salted fish-Heterophyes heterophyes Parasite

Heterophyes Parasite has a oval shape,tick and light brown colour.Is formed of body and tail,2 dark eyes spots,is a oral sucker and has 7 pairs of penetration glands.

The adult worms live in the samll intestine of man,dog,cat and other fish eating animals.Eggs are discharged with faeces.
The eggs does not hatch in water but is ingested by snail that lives in brackish water.Whitin the snail and develops into other generation that leave the sanil to the water.This penetrate the skin of fishes (like Bolthy and Boury fishes of Egypt).In the muscle of fish the parasite reach the infective stage.So,the cycle needs 2 intermediate hosts.

The definitive host is infected by eating raw fish,improperly cooked (for exemple grilled) or freshly salted fish (less then 10 days).
In the small intestine,the cyst wallis dissolved and start the infective stage.Eggs appear in faeces 2-3 weeks after infection.

Symptomatology:
-Mild inflammation and superficial necrosis of the mucous at the site of attachment.
As symptoms: colicky pain,diarrhoea with mucus and blood.
-Eggs emboli: eggs may find their way into circulation where they are carried to ectopic sites (for exemple heart and can lea to myocarditis and heart failure).

Eggs can be detected in faeces by laboratory test.

Infection by heterophyes parasite can be controled by periodic examination of water (avoiding defecation in water),by mass treatment and proper cooking of fish.

READ MORE:
Parasites that can infect humans who eat raw fish

Whipworm-Parasite of unwashed hands,unwashed vegetables and unsanitary water

Trichocephalus Trichiurus known by common name as Whipworm is more prevalent in poor sanitary areas and is more common in children.

Man is the only definitive host.The adult worms live in the caecum and appendix with the thin and anterior portion embedded in the mucosa parallel to the digestive tract.In heavy infection,it may extend into the colon and even the rectum.Each female deposits 3000-6000 eggs a day.

Under favourable conditions like warm regions,shaded,moist soil,the eggs develops a rhabditiform larva within 3 to 4 weeks.

Man parasites infection by ingestion of mature egg with contaminated food (green raw vegetables)unsanitary water and unwashed hands.In the lawer part of the small intestine,the larva hatches through one of the poles of the egg,passes directly to the caecum,moults 4 times and becomes sexually mature.
Egga appears in faeces 3 months after infection.

In light infection no symptoms,presence of the parasite is discovered only on stool examination.
The heavy infection results in:
-extensive inflammation and irritation of the mucous membrane at the points of attachement with hemorrhage that leads to submucosal absesses and ulcers.Appears abdominal pain,most commonly in the lower right quadrant of the abdomen,nausea,vomiting and diarrhoea with streaks of blood.
-appendicitis
-anaemia
-dysentery.

Whipworm can be detected by faeces laboratory.

Hydatid Worm-The parasite infection from dog to man

The hydatid worm have a size of 3-6 mm,adult worms live in the small intestine of dogs and other canines,but never man.
Eggs discharged in faeces are swallowed by intermediate host as sheep,cattle and occasionaly man.
Man ingests the egg along food or water contaminated with faeces of dog or by handling dogs whose hairs are usually contaminated with eggs.


In the intestine the hatches,penetrates the mucosa,to reach different organs where it develops into hydatid cyst.The liver is the common affected organ followed by the lung,then the brain,bone,spleen,kidney,muscles,heart and eyes.

When the cyst is ingested by dog and other canines,the animals develop the adult worms.Since cysts in the viscera of man are not available for dog,the life cycle of the parasite comes to a blind end.

Symptomatology:
Local effects: depend on the size and site of the cyst:
cough,pain,symptoms of increased intracranial tension,epilepsy,bone erosion,fracture.

Diagnosis:
Radiological: X-ray,ulrasonography,C.T scans.
Puncture and aspiration to demonstrate hydatid sand.

Treatment:
-Surgical removal
-Sterilization.

Control and Prevention:

For the dog:
-periodic examination and treatment of pet
-elimination of stray ones
-infected organs in slaughter houses should be destroyed to prevent infection of dogs

For the man:
-avoid food and drink contaminated with faeces of dogs (avoid contact with faeces r the dog presence in food places)
-avoid contact with possible contaminated dogs
-wash the hands after you play with the dog.

Fish Parasites that can infect humans who eat raw fish

Broad Tapeworm or Fish Tapeworm -Some flat worms,including tapeworms have become highly modified and lives as parasites in migratory marine fish (such as salmon) that become infected by the laerves when they eat either the crustaceans or other infected fish.The adult tapeworm lives in fish eating mammals and may infect human who eat raw fish.

Can appear in lake regions from Europe,America,Russia,Japon,Central Africa.
The broad tapeworm has a size of 3-10 metres in lenght and spoon shape.

Adult worms live in the small intestine of man,dog,cat and fish eating animals.Eggs are discharged with faeses.In fresh water the egg matures and hatches within 2 weeks.

Is necessary a detection of eggs in faeces and a blood test for diagnosis.

Mosquitos-Transmission of disease

They are more common in worm,tropical and temperate countries.
They are small insects of 3-10 mm,the body covered with scales,one pair of compound eyes,one pair of long antenne and mouth.

Female are adapted for percing and sucking blood with the blood feeder formed of: uper lip,tongue with salivary duct running along it,one pair of mandibles and one pair of maxille with separrated tips,lower lip (this does not enter the wound of bite when mosquito feeds).The secretion of saliva causes hyperemia and prevent coagulation of blood.

The male suck only and feeds on flower juice (vegetarian) and has no role in disease transmission.

The life cycle takes 2 weeks.Fertilised female need a blood meal for development of eggs and eggs are laid on the surface of water either singly or in group cemented together.It hatches within 3-4 days at the suitable temperature.
The larva lives in water and feeds on organic matter and plants.

Transmission of disease:
By bite the female mosquito can transmit the fallowing diseases:
-human malaria
-tissue namatode (tissue worm)
-viral encephalitis
-rift valley fever virus: viral disease.
-bird malaria
-dengue fever virus: a viral disease similar to influenza characterized by fever,headache,bone aches and severe joint pains that last for about one week.
-yellow fever virus: is a qurantinable viral disease wich is endemic in Tropical africa and South America).

Pork Meat- possible source of TRICHINOSIS

Trichinosis is a parasitic disease of man that gives two pathological conditions caused by:
-adult worm in small intestine.
-encycted larvae in skeletal muscles.

Trichinella spiralis worm is a round worm with male of 1.5 mm and female of 3 mm long.It inhabits small intestine attached to or buried in the mucosa.

Reservoirs of Infection:
The pig with trichinella cysts in muscles is the only intermediate host of human infection.

The pig gets infected from rats,dogs,cats,swine and other animal reservoirs which have both worms in intestine and encysted larve in muscles.
Infection spread inbetween animals when an animal feed on waster contamining infected tissues of another animal and ingests the infective encysted larve.The pig can thus be infected this way to become the only intermediate host of human infection.

Modes of Infection:
Man is infected with both worms and cysts.

Infection with adult worms occurs first by ingestion of insufficiently cooked or processed raw,meat (muscle) of infected pig:encysted larve in muscle of pig are liberated in small intestine and develop into adult worms.

Infection with encysted larve: man is then exposed to autoinfection,where fertilized female worm burrows into th eintestinal mucosa to deposit larve.Larve penetrate the intestinal wall to be carriedby the circulation to different skeletal muscle where the encyst (forming encyst larve).

Symptoms:
Adult worms in intestine cause intestinal disturbance.
Encysted larve in muscle gives different muscle manifestations.

Trichinosis is a problem in communities commonly consuming pork (meat of swine) and pork products,under insanitary conditions like:
-No clean feeding of pigs: they are fed on wastes containing tissue of infected animals (dogs,cats,rats) and so get infected with encysted larve in muscle.
Insufficient cooking and processing of infected meat,where cysts remain viable.

Prevention of Trichinosis:
1.Measures for pig: the intermediate host of human infection.
-sanitary raising and feeding to prevent being infected from contaminated wastes.
-meat sanitation: examining muscle of slaughtered pig,efficient cooking of meat,to destroy the encysted larve,efficient meat processing in factories.

2.Health Education of those consuming pork for porkborne infections and how to be avoided.

What are the infections transmitted by pork?
Parasitic and bacterian infections.

1.Parasitic Infections:
-Trichinosis : both dult worms in samll intestine and ecysted larve in skeletal muscle.
-Taeniasis solium : infection with worms in small intestine.
2.Bacterial Infections: Salmonellosis and Brucellosis.

Pork transmits two parasitic infections.In both,man is not only infected with adult worm in small intestine,but is also exposed to infection with larva stage in different parts of the body,causing cysticercosis and trichinosis that may be serious.

Parasitic Disease transmitted by ingestion-ASCARIASIS

Ascariasis is chronic intestinal parasitic disease.
Ascariasis lubricoides are nematode that lives in the lumen of small intestine,with male of 15-25 cm and female of 20-40 cm worms.
Each female worm puts thousands of eggs every day,to find exit in faeces.

Infective stage: passed eggs are not infective.They develop outside the body in 2-3 weeks to become embryonated.
Embryonated egg in polluted environment is the infective stage.It is resistant to desiccation and disinfectants and remains viable and infective under favourable environmental conditions for around three months.

Modes of Transmission:
Foodborne and hand to mouth infection (ingestion infection).
1.Foodborne infection: consuming embryonated egg in contaminated food,specially salad vegetables and pollutes water.
2.Hand to mouth infection: when the hand is contaminated with eggs-containing dust.Children are particularl affected,when hands get contaminated on playing in the road and are infected through either:
   -putting contaminated fingers in the mouth
   -taking food without handwashing.

How ascariasis eggs reach food?
-using fresh human fertilizer for vegetables
-contamination of food with eggs-containing dust (from human excreta)
-flies may have potential.

How ascariasis rech dust?
Through contaminating the soil with human excreta,by promiscuous defecation in underdeveloped areas.

Why there is no faeco-oral infection for ascariasis?
Because eggs passed in faecas are not infective,after developing in to embryonated egg in 2-3 weeks.That is also whyinfected food handlers do not spread infection .

Ascariasis cycle in the body:
Ingested infective eggs hatch in the small intestine to give larve that penetrate the intestine,to be carried by the circulation to the lungs where they reach the alveoli,then up in the airways to the pharynx,to be swallowed and backn to small intestine.
Migration cycle takes about 10 days.

Incubation period: about two months from ingestion of embryonated eggs until eggs first appear in stools.

Symptoms:
Manifest cases commonly show:
-Respiratory manifestation :spasms of coughing,usually nocturanl and pneumonitis due to petechial bleeding caused by migrating larve in the lungs.
-Intestinal disorders: abdominal discomfort and colic.
-Nutritional deficiency: du to anorexia,impaired digestion and protein absorption and loss of nutrientts consumed by parasite (proteins,vitamins).
-Others: restless sleep and griding of teeth,commonly in children.

Ascaris is diagnosed by indentifying the eggs in smear of faeces.

Predisposing Factors:
-Promiscuous defecation that contaminates the soil with ascaris eggs.
-Fertilizing vegetables with fresh human fertilizer.
-Ingestion of salad (fresh vegetables) without thorough washing.
-Neglecting care of children who play in the road and get hands contaminated with eggs carrying dust and not washed.

Prevention of Ascariasis:
1.Sanitation of environment:
-safe water supply,food sanitation.
-providing rural area with sanitary convenient latrines and sanitary disposal of wasters.
To be used for fertilization of vegetables human excreta must be stored in covered packed heaps for at least six weeks.
-fly control.

2.Health education of the public:
-using water closetof latrines and avoid promiscuous defecation.
-thorough washing of uncooked vegetables.
-handwashing on returning home and before food.
-supervision of children on playing outdoors and advise them to avoid putting fingers in the mouth and wash hands when necessary and before food.

House fly-Transmission of disease

Characteristics of the house fly:

Is a medium size fly about 1cm in length,greyish colour.The head carries:2 big compound eyes(close in male,apart in female)and 3 simple eyes in between;2 antennae,mouth parts adapted for sucking.

The life cycle:
Has a complete metamorphosis,the cycle takes one week.female deposits eggs in batches(50-100 at a time0 on organic decayed matter,garbage.The eggs are banana shaped with 2 longitudinal riges,creamy withe in colour,1 mm in length and hatches in 10 hours.

Habits:
-live in contacts with man
-active in daytime and rest at night(corners of rooms,ceilling)
-prevalent all the year round in tropics while in temperate zones the number falls strongly or may even dissapear in cold weather.
-feed usually on liquid or semi-liquid substances beside solid material which has been softened by saliva or vomit.

The importance role of house fly in transmitting diseases to man is due to:
-their habits of standing and feeding on human excretions and human food,
-their high intake of food with constant vomiting and deposition of faeces.

MEDICAL IMPORTANCE:
Transmission of diseases:
-bacterial diseases:enteric fevers,cholera,bacillary dysentery,wound infection.
-viral diseases:poliomyelitis,hepatitis,tranchoma.
-parasitic diseases.
The mechanism of transmission;mechanical transmismission along the mouth parts,hairs covering the body and legs and faeces.

Control:
-screening of windows and doors
-covering the food
-fly paper,traps and mechanical knocking down
-insectocides
-proper disposal of garbage
-sanitary disposal of excreta
-insecticides specially for heaps of manure,garbage,animal stables
-health education.