ENCEPHALITIS

Transmission:	Mosquitoes
Symptoms:	If the disease develops, symptoms usually include high fever, aches, stiff neck and weakness. More severe cases may include vomiting, diarrhoea, mental impairment or coma. Many people who contract the virus never develop the disease or any of its symptoms. Of those who actually develop the disease, up to 40% of the cases may result in death.
Treatment:	There is no known cure, only supportive treatment.

MALARIA

Transmission:	Anopheles mosquitoes, which feed from dusk to dawn. The disease is present in almost all countries in the tropics and sub-tropics.
Symptoms:	In early stages symptoms are flu-like i.e. fever, chills, headache and muscle ache. Symptoms may occur 7 to 8 days after infection. Some symptoms may reappear months or years after infection if not treated properly. Death occurs in 2% of cases.
Treatment:	Antibiotics. Anti-malarial drugs should be taken as prophylaxis if travelling in high risk areas.

DENGUE FEVER

Transmission:	Transmitted to humans by urban Aedes mosquitoes. Most cases are found in tropical areas of Asia, Africa and the Americas.
Symptoms:	'Classic' forms include high fever, headaches, aches, sore throat and a rash. The rash appears 3-4 days after symptoms start and may not be visible in persons of darker skin colour. Symptoms generally last 5-7 days, followed by several weeks of fatigue and weakness. More severe forms of dengue fever can include symptoms such as fever, vomiting, headaches, coughing and abdominal pain.
Treatment:	Treatment is supportive only. Low mortality rate.

LYME DISEASE

Transmission:	Carried by deer ticks primarily in the East and Mid-West USA, and western black-legged ticks in the Pacific coastal states. Found in UK and Europe particularly Eastern Europe. These are small arthropods, often no larger than a pinhead, which are difficult to detect and whose bites frequently go unnoticed.
Symptoms:	In about 50% of cases, the first sign is a red blotch or bull's eye pattern rash. If untreated the rash may double or quadruple in size. The rash does not always occur at the bite site, and may appear at the armpit, groin or the back of the knee. Other signs include flu-like symptoms - chills, fever and fatigue. If untreated, Lyme Disease may cause problems that appear months or even years later, including severe headaches, arthritis, nervous system disorders and heart trouble. Its effects can last a lifetime and disable you.
Treatment:	If caught early, most cases of Lyme Disease can be treated with oral antibiotics. However, some people will require intravenous antibiotic treatment.

Ticks can also cause Encephalitis, Rocky Mountain Spotted Fever and Human Granulocytic Erlichiosis (HGE)