Parasitic infection due to protozoa of genus Plasmodium transmitted by the female Anopheles mosquito. There are four plasmodia species: P. falciparum, P. vivax, P. malariae, P. ovale.
— Malaria is an acute and chronic protozoan illness characterized by paroxysms of fever, chills, sweats, fatigue, anaemia and splenomegaly.
— Falciparum malaria (severe and complicated malaria) is associated in varying degrees with the following clinical signs:
Cerebral: mental clouding, coma, convulsions, delirium and occasionally localizing signs Hyperpyrexia (>40.5ºC) Haemolysis, oliguria, anuria, pulmonary oedema and macroscopic haemoglobinuria
— Diagnosis is made by presence of protozoa in the blood in thick and thin smear slides. Thick smear for easy detection of parasite and thin smear for identification of species. Note that blood films may be negative even in a severe attack because of sequestration of parasites in the deep capillaries
Principles of therapy
1. All fever cases without any other obvious causes should be presumed as malaria cases and antimalarial drug be given preferably after taking blood smear.
2. Chloroquine is the main antimalarial drug and it is to be used as first line of treatment for the treatment of uncomplicated malaria.
3. In high-risk areas presumptive treatment 25 mg/kg of Chloroquine base is to be given on 3 consecutive days with a single dose of Primaquine 0.75 mg/kg on the first day. High risk area is defined as follows:
i. Recorded deaths due to malaria (on clinical diagnosis or microscopic confirmation) with P. falciparum infection during the transmission period in an endemic area during any of the last 3 years.
ii. Doubling of slide positivity rate (SPR) during the last 3 years provided the SPR in second or third year reaches 4% or more or the average SPR of the last year is 5% or more.
iii. P. falciparum is 30% or more provided SPR is 3% or more during any of the last 3 years.
iv. An area having a focus of chloroquine resistant P. falciparum.
4. In the low risk areas, presumptive treatment 10 mg/kg Chloroquine single dose.
5. Resistance should be suspected if inspite of full treatment and no history of vomiting and diarrhoea, patient does not respond within 72 hours parasitologically. Such patients should be given alternative drug i.e. Sulfa-pyrimethamine (S-P) combination.
6. S-P combination is the antimalarial drug of choice in P. falciparum resistant to chloroquine. The dose is 25 mg/kg of sulfa + 1.25 mg/kg of pyrimethamine which is 3 tablets for the adult (single dose).
7. The dose of Primaquine for P. vivax cases is 0.25 mg/kg daily for 5 days to prevent relapse and for P. falciparum 0.75 mg/kg single dose for gametocidal action.
8. Mefloquine can be given to chloroquine/other antimalarial resistant uncomplicated P. falciparum cases only.
9. Resistance to Chloroquine
— There must be an evidence of falciparum positive blood slide on the first and third days of treatment. WHO classifies resistance to chloroquine into 3 types.
— R1: total disappearance followed by reappearance of the parasite.
— R2: noticeable fall without disappearance of the parasite.
— R3: parasite level almost unchanged, indeed, increased.
Before labeling resistance verify
— that treatment has in fact been taken.
— that the correct dose for weight has been prescribed.
— the patient has not vomited within 30 min of taking medication.
— that there has not been under-dosage due to confusion between the expression of the dosage as a chloroquine base and as a chloroquine salt. Equivalence between salt and base:
130 mg sulphate=150 mg phosphate or diphosphate = 100 mg base.
200 mg sulphate=250 mg phosphate or disphosphate= 150 mg base.
10. In Pregnant woman and infants, primaquine is contraindicated. As no data is available to suggest the safety of artemisinin derivatives in this group, the same is not recommended.
Patients of uncomplicated malaria can be managed at primary level but patients with severe malaria with complications should be admitted and managed in a hospital where facilities for detailed investigations and blood transfusion exists.
A. Presumptive treatment in uncomplicated malaria
Low Risk Area:
Single dose of Tab. Chloroquine phosphate 10 mg/kg, (maximum dose is 600 mg) to all suspected malaria cases.
High Risk Area
Chloroquine Day 1 base 10 mg/kg (600 mg adult)
Primaquine Day 1 0.75 mg/kg (45 mg adult)
Chloroquine Day 2 base 10 mg/kg (600 mg adult)
Chloroquine Day 3 base 5 mg/kg (300 mg adult)
B. Confirmed cases of malaria
1. Tab. Chloroquine as in presumptive treatment in “high risk area”.
(a) In P. vivax Tab. Primaquine 0.25 mg/kg/day for 5 days.
(b) In P. falciparum Primaquine 0.75 mg/kg as a stat (single dose).
In high risk areas where presumptive treatment with 500 mg Chloroquine base and 45 mg Primaquine (adult dose) has been given, Chloroquine need not be administered again, but Primaquine must be given for 5 days.
C. Chloroquine resistant P. falciparum case: In P. falciparum cases not responding to chloroquine, second line of treatment must be given as a single dose of Sulphalene/Sulphadoxine (1500 mg) + Pyrimethamine (75 mg) in dose of 25 mg/kg of Sulpha (3 tablets in adults) followed by Primaquine (45 mg).
D. In severe and complicated malaria cases
In severe and complicated P. falciparum malaria, irrespective of chloroquine resistance status of the area Inj. Quinine salt 10 mg/kg 8 hourly IV in 5% dextrose saline is preferred. Patients should be switched over to oral quinine as early as possible and oral dose 10 mg/kg 8 hourly not exceeding 2 g in a day in any case.
Minimum total duration for quinine therapy should be for 7 days including both parenteral and oral doses.
Or In nonpregnant adults and in case of G-6 PD deficiency (capsule and tablet forms of these derivatives are not recommended for use in India)
Artemisinin derivatives (any of the following)
Dosages are as follows:
Inj. Artemisinin: 10 mg/kg once a day IV for 5 days, with a double divided dose administered on the first day;
Inj. Artesunate: 1 mg/kg (two doses) IM/IV at an interval of 4-6 hours on the first day followed by 1 mg/kg once daily for 5 days.
Inj. Artemether: 1.6 mg/kg (two doses) IM at an interval of 4-6 hours on the first day followed by 1.6 mg/kg once daily for 5 days. Inj. Artether: 150 mg daily IM for 3 days.
Chemoprophylaxis in selective cases
Chemoprophylaxis is recommended for a) pregnant women in high risk areas and b) travelers including service personnel who temporarily go on duty to high malarious areas. Chemoprophylaxis is to be started a week before arriving to malarious area for visitors and for pregnant women prophylaxis, it should be initiated from second trimester.
Chloroquine sensitive area
— Start with loading dose of Tab. Chloroquine 10 mg/kg, followed by a weekly dose of 5 mg/kg. This is to continue till 1 month after delivery in case of pregnancy and in travelers till one month after return from endemic area. The terminating dose should be 10 mg/kg along with 0.25 mg/kg of Primaquine for five days.
(CAUTION: In pregnancy, Primaquine should not be given)
— Chemoprophylaxis with chloroquine is not recommended beyond 3 years because of its cumulative toxicity.
— In chloroquine resistant areas Chloroquine 5 mg/kg weekly and Proguanil 100 mg daily.
— To take measures to stop mosquito breeding and protection from mosquitos e.g. mosquito nets, repellents, long sleeves, long trousers etc.
— Fever without any other signs and symptoms should be reported to nearest health facility.
— Chloroquine should be given with plenty of water after food and not on empty stomach. If chloroquine syrup is not available for children, the tablet should be crushed and given with honey or thick syrup.
— Watch for side effects of drugs prescribed. Chloroquine may cause nausea, vomiting and diarrhoea, mild headache and skin allergy/rash.
— If vomiting occur within 30 minutes of chloroquine intake repeat the dose of chloroquine.
— Chloroquine and sulphadoxine + pyrimethamine should not be given if patient is suffering from G-6 PD deficiency.
— Patients should be educated about symptoms of cerebral malaria, and should seek medical help immediately on occurance of these symptoms.