What is meant by waste disposal ?

During the course of teaching I found that students considered the collection of wastes in dustbins as disposal of waste. This is actually waste collection and not disposal. The steps involved in waste management is waste generation, collection, transportation and disposal. Waste disposal is the final treatment and disposal in waste management process. For more details click on the following link which tells how the waste disposal is defined by Basel Convention, European Union and OECD/Eurostat Joint questionnaire http://scp.eionet.europa.eu/definitions/disposal

If I started Hepatitis B immunization and did not complete the course, what should I do ?

According to guidelines created by the Centers for Disease Control and Prevention (CDC) you do not have to restart the vaccine series if you received only one or two doses - even if it has been a few years since your last dose of the vaccine. You only need to complete the series by getting the remaining shot(s).

Recrudescence and relapse in Malaria

Recrudescence is a re-attack of malaria because of the surviving malaria parasites in red blood cells. Characteristic of P.malariae infections. This may be short term or delayed.

Relapse is a re-attack of malaria because of infection by the malarial parasites which were surviving in the liver (i.e. hypnozoites). This is usually a delayed feature.

Vector competence and vectorial capacity

Vector competence refers to the ability of mosquitoes to receive a disease agent microorganism (arbovirus etc.) from the reservoir host and then later transmit the infectious agent to another susceptible host.
Vectorial capacity includes a number of factors like vector competence, mosquito population density, host preferences, biting rate, immunity of the mosquitoes etc.
To be an effective vector, mosquitoes must have a high vector competence and vectorial capacity.

In infectious disease epidemiology; what is the difference b/w vehicle and fomite ?

A vehicle is a substance which can carry a microorganism into your body. e.g. air, water or food. A fomite is an object which is capable of retaining a microorganism, and may be a source of infection.