Communicable Diseases Module: Introduction

Introduction to the Communicable Diseases Module

Communicable diseases caused by bacteria, viruses, protozoa, fungi and parasites, make a huge contribution to the burden of disease, disability and death in low- and middle-income countries like Ethiopia. The emergence of HIV/AIDS as a global pandemic, the resurgence of tuberculosis co-infection with HIV, and the rapid spread of fatal outbreaks of influenza, have also brought communicable diseases back onto the agenda of health services in high-income countries. The six leading groups of infectious diseases (acute respiratory infections, HIV/AIDS, diarrhoeal diseases, tuberculosis, malaria and measles) together cause over 11 million deaths worldwide every year, and blight the lives of tens of millions more who are living with their chronic or recurrent effects. These high-profile diseases are relatively well publicised across the world, and are subject to major research into vaccines and treatments. By contrast, at least 1 billion people are affected by the so-called ‘neglected tropical diseases’, including leprosy and schistosomiasis, and/or by intestinal parasites such as tapeworm and hookworm.

Some communicable diseases are easily preventable through simple measures such as vaccination and changes in human behaviour (for example, handwashing with soap). However, the transmission of infectious agents will be difficult to reduce to the levels seen in wealthier nations without significant reductions in the proportion of people living in impoverished social circumstances, with poor nutrition that leaves them more vulnerable to infection, without housing that is secure from disease-carrying pests, and without access to clean drinking water, improved sanitation or the safe disposal of household waste. Strenuous efforts are being made to address these problems in Ethiopia, as elsewhere in Africa and in other developing countries.

To prevent or control the major communicable diseases in Ethiopia, a concerted effort by the nation’s health workers, the government, development partners and community members is crucial. Together with the practical skills training associated with this Module, Communicable Diseases will help you to acquire the basic skills and knowledge to reduce the burden of mortality and morbidity in your community through the detection, prevention and treatment of common infections.

Communicable Diseases is divided into four Parts. In Part 1 (Study Sessions 1–12), you will first learn the basic concepts in the transmission, prevention and control of communicable diseases, which forms the foundation for all the sessions in later parts of the Module. Next we discuss some important vaccine-preventable diseases (neonatal tetanus, bacterial meningitis, measles, polio and hepatitis B). Part 1 then focuses on malaria and its mosquito vectors: its transmission, its diagnosis based on clinical signs and the malaria rapid diagnostic test (RDT), malaria case management, vector control methods, and the management of epidemics.

Part 2 (Study Sessions 13–19) deal with tuberculosis (TB) and leprosy, which are caused by different Mycobacteria. In both diseases the symptoms are due to inflammation and tissue destruction in the infected body parts. The diagnosis, treatment and prevention of these disabling diseases are covered in detail, including the rapid diagnostic test for TB and assessments of disability and nerve damage in people with leprosy.

Part 3 (Study Sessions 20–31) is about the human immunodeficiency virus (HIV) and the spectrum of HIV diseases leading to acquired immune deficiency syndrome (AIDS). It includes opportunistic infections and other sexually-transmitted infections (STIs). The focus is on diagnosis, treatment options and regimens, and prevention of infection and HIV transmission, including from mother to child, and protection from accidental HIV infection in health workers. It also covers positive living for people with HIV and palliative care for those who are dying.

Part 4 (Study Sessions 32–42) completes the Module by discussing the diagnosis, treatment, prevention and control of other communicable diseases of public health importance, including diarrhoeal diseases, intestinal parasites, acute respiratory infections and otitis media, relapsing fever, typhus, neglected tropical diseases, zoonoses, trachoma and scabies. The Module ends with three study sessions on integrated disease surveillance and response, and epidemic investigation and management.