Two Communicable Diseases in Annang Community of Akwa Ibom State

TWO COMMON COMMUNICABLE DISEASES INANNANG COMMUNITY IN AKWA IBOM STATE

WRITTEN BY

WILLIAMS, I. BONIFACE

OUTLINE

Introduction

1.1 Typhoid Fever

1.1.1 Epidemiology

1.1.2 Clinical Features

1.1.3 Transmission

1.1.4 Prevention and Control

1.2 Acquired Immune Deficiency Syndrome (AIDS)

1.2.1 Epidemiology

1.2.2 Clinical Features

1.2.3 Transmission

1.2.4 Prevention and Control

Summary

References

INTRODUCTION

Communicable diseases spread easily from person

to person in Annang community and can cause many

illnesses and deaths. Annang community cuts across

eight local government areas in Akwa Ibom State of

Nigeria (Umoh, 2004). This group of people consist of

over one million people in the western part of Akwa

Ibom state (Brink, 1989). This research paper

highlights the epidemiology, clinical features, and

mode of transmission, prevention and control

mechanisms of Typhoid fever and Acquired

Immunodeficiency Syndrome (AIDS) in Annang community.

1.1 TYPHOID FEVER

Typhoid fever, also known as enteric fever, is a

potentially fatal multi-systemic illness caused

primarily by Salmonella typhi. Typhoid fever is

characterized by severe systemic illness with fever

and abdominal pain (Fraser Goldberg, Acosta, Paul and

Leibovici, 2007). The organism classically responsible

for the enteric fever syndrome is Salmonella enterica

serotype Typhi (formerly Salmonella typhi). Other

Salmonella serotypes, particularly Salmonella enterica

serotype paratyphi A, B, or C, can cause a similar

syndrome; however, it is usually not clinically

useful or possible to reliably predict the causative

organism based on clinical findings (Parry and

Beeching, 2009). The term “enteric fever” is a

collective term that refers to both typhoid and

paratyphoid fever.

Salmonella typhi has been a major human pathogen for

thousands of years, thriving in conditions of poor

sanitation, crowding, and social chaos. It may have

been responsible for the Great Plague of Athens at

the end of the Pelopennesian War (Farmer, 2003). The

name Salmonella typhi is derived from the ancient Greek

‘typhos’, an ethereal smoke or cloud that was believed

to cause disease and madness. In the advanced stages

of typhoid fever, the patient's level of

consciousness is truly clouded. Although antibiotics

have markedly reduced the frequency of typhoid fever

in the developed world, it remains endemic in

developing communities and countries (Cuaha, 2004).

The protean manifestations of typhoid fever make

this disease a true diagnostic challenge. The classic

presentation includes fever, malaise, diffuse

abdominal pain, and constipation. Untreated typhoid

fever is a gruelling illness that may progress to

delirium, obtundation, intestinal hemorrhage, bowel

perforation, and death within one month of onset.

Survivors may be left with long-term or permanent

neuropsychiatric complications (Cuaha, 2004).

1.1.1 EPIDEMIOLOGY

Typhoid fever is endemic throughout the Annang

community including Africa and Asia and persists in

the Middle East, a few southern and eastern European

countries and central and South America. In the US

and most of Europe, apart from occasional point

source epidemics, typhoid is predominantly a disease

of the returning traveller (Shapiro, Rambaut and

Gilbert, 2006). A recent study estimated there to be

approximately 22 million cases of typhoid each year

with at least 200 000 deaths (Fraser et al., 2007).

However, the true magnitude is difficult to quantify

because the clinical picture is confused with many

other febrile illnesses and most typhoid endemic

areas such as this community (Annang community) lack

facilities to confirm the diagnosis. Data from

placebo groups in large-scale field trials of typhoid

vaccines and population-based epidemiology studies

show annual incidence rates ranging from 10 to 1000

cases per 100 000 people.

Typhoid fever is more common in children and

young adults than in older patients (Shapiro et al.,

2006). In Annang community, typhoid fever is most

prevalent in impoverished areas that are overcrowded

with poor access to sanitation. Non-epidemic

incidence estimates suggest that south-central Asia,

Southeast Asia, and southern Africa are regions with

high incidence of Salmonella typhi infection (more than

100 cases per 100,000 person years) (Papagrigorakos,

Yapijakis, Synodinos, and Baziotopoulou-Valavani, 2006)

Other regions of Asia and Africa, Latin America, the

caribbean, and Oceania have a medium incidence of 10

to 100 cases per 100,000 person years. These

estimates, though, are limited by lack of consistent

reporting from all areas of the world and are based

on extrapolation of data across regions and age

groups. As an example, the incidence estimates within

Africa are based upon reports from Egypt and South

Africa only and thus may not be accurately defined.

The incidence of typhoid in endemic areas is

typically considered to be low in the first few years

of life, peaking in school-aged children and young

adults and then falling in middle age. Older adults

are presumably relatively resistant due to frequent

boosting of immunity, but the apparent low incidence

in pre-school children contrasts with the high

incidence of most other enteric infections at this

age in these countries (Cooke, Wain and Threlfall,

2006).

Because humans are the only reservoir for

Salmonella enterica serotype Typhi, a history of travel

to settings in which sanitation is poor or contact

with a known typhoid case or carrier is useful for

identifying people at risk of infection outside of

endemic areas, although a specific source or contact

is identified in a minority of cases (Cooke et al.,

2006).

The faeces of persons who have unsuspected

subclinical disease or are carriers are a more

important source of contamination than frank clinical

cases that are promptly isolated, e.g. when carriers

working as food handlers are ‘shedding’ organisms.

Many animals including cattle, rodents and fowl, are

naturally infected with a variety of Salmonella and have

the bacteria in their tissues (meat), excreta or

eggs. The high incidence of Salmonella in commercially

prepared chickens has been widely publicised. The

incidence of typhoid fever has decreased, but the

incidence of other Salmonella infections has increased

markedly in the United States. The problem probably

is aggravated by the widespread use of animal feeds

containing antimicrobial drugs that favour the

proliferation of drug-resistant Salmonella and their

potential transmission to humans (Cooke et al., 2006).

1.1.2 CLINICAL FEATURES

The onset is usually insidious but in children

may be abrupt, with chills and high fever. During the

prodromal stage, there is malaise, headache, cough

and sore throat, often with abdominal pain and

constipation. The fever ascends in a step-ladder

fashion. After about 7-10 days the fever reaches a

plateau and the patient looks toxic, appearing

exhausted and often prostrated. There may be marked

constipation, especially in early stage or “pea-soup”

diarrhoea as stated by Papagrigorakis et al. (2006).

There is marked abdominal distention. There is

leukopenia and blood, urine and stool culture is

positive for Salmonella. If there are no complications

the patient’s condition improves over 7-10 days.

However, relapse may occur for up to 2 weeks after

termination of therapy.

During the early phase, physical findings are

few. Later, spleenomegaly, abdominal distension and

tenderness, relative bradycardia, dicrotic pulse,

and occasionally meningismus appear. The rash (rose

spots) commonly appears during the second week of

disease. The individual spot, found principally on

the trunk, is a pink papule 2-3 mm in diameter that

fades on pressure. It disappears in 3-4 days (Cuaha,

2004)

Cooke et al. (2006) explained that serious

complications occur in up to 10 per cent of typhoid

fever patients, especially in those who have been ill

longer than 2 weeks, and who have not received proper

treatment. Intestinal haemorrhage is manifested by a

sudden drop in temperature and signs of shock,

followed by dark or fresh blood in the stool.

Intestinal perforation is most likely to occur during

the third week. Less frequent complications are

urinary retention, pneumonia, thrombophlebitis,

myocarditis, psychosis, cholecystitis, nephritis and

osteomyelitis.

Estimates of case fatality rates of typhoid fever

range from 1 per cent to 4 per cent; fatality rates

in children aged less than 4 years being ten times

higher (4.0%) than in older children (0.4%). In

untreated cases, the fatality rates may rise to 10-20

per cent (WHO, 1987)

1.1.3 TRANSMISSION

Salmonella typhi has no non-human vectors. The

following are modes of transmission:

Oral transmission via food or beverages handled

by an individual who chronically sheds the

bacteria through stool or, less commonly, urine;

Hand-to-mouth transmission after using a

contaminated toilet and neglecting hand washing

hygiene;

Oral transmission via sewage-contaminated water

or shellfish (especially in the developing world)

(Bhutta, Khan and Molla, 1994).

An inoculum as small as 100,000 organisms causes

infection in more than 50% of healthy volunteers.

(Bhutta et al.,1994).

Fecal-Oral Transmission Route:

In 1873, William Budd described the contagious

nature of typhoid disease and incriminated fecally

contaminated water sources in transmission (Dutta,

Mitra and Dutta, 2001).

The bacteria that cause typhoid fever spread

through contaminated food or water and occasionally

through direct contact with someone who is infected.

In developing nations, where typhoid is endemic, most

cases result from contaminated drinking water and

poor sanitation. The majority of people in

industrialized countries pick up the typhoid bacteria

while travelling and spread it to others through the

faeco-oral route.

This means that Salmonella typhi is passed in the

faeces and sometimes in the urine of infected people.

You can contract the infection if you eat food

handled by someone with typhoid fever who hasn't

washed carefully after using the toilet. You can also

become infected by drinking water contaminated with

the bacteria (Wallace, Yousif and Mahrois, 1993).

1.1.4 PREVENTION AND CONTROL

The prevention and control of typhoid fever is well

within the scope of modern public health. This is an

accomplished fact in many developed countries. There

are generally three lines of defence against typhoid

fever (Effa, Lassi and Critchley, 2011): Control of

reservoir, Control of sanitation and Immunization.

The weakest link in the chain of transmission is

sanitation which is amenable to control.

Control of Reservoir:

The usual methods of control of reservoir are their

identification, isolation, treatment and

disinfection.

a)Cases:

i) Early diagnosis: this is of vital importance as

the early symptoms are non-specific. Culture of

blood and stools are important investigations

in the diagnosis of cases.

ii) Notification: this should be done where such

notification is mandatory.

iii)Isolation: since typhoid fever is infectious

and has a prolonged course, the cases are

better transferred to a hospital for proper

treatment, as well as to prevent the spread of

infection.

iv) Treatment: the fluoroquinolones are widely

regarded as the drug of choice for the

treatment of typhoid fever.

v) Disinfection: stools and urine are the sole

sources of infection. They should be received

in closed containers and disinfected with 5

percent cresol for at least 2 hours.

vi) Follow-up: follow-up examination of stools and

urine should be done for Salmonella typhi 3-4

months after discharge of the patient, and

again after 12 months to prevent the

development of the carrier state (Effa et al.,

2011).

b)Carriers:

Since carriers are the ultimate source of typhoid

fever, their identification and treatment is one of

the most radical ways of controlling typhoid fever.

The measures recommended are (Bhutta et al., 1994);

i) Identification: Carriers are identified by

cultural and serological examinations.

ii) Treatment: The carrier should be given an

intensive course of ampicillin or amoxicillin

(4-6g/day) together with probenecid (2g/day)

for 6 weeks

iii)Surgery: Cholecystectomy with concomitant

ampicillin therapy has been regarded as the

most successful approach to the treatment of

carriers.

iv) Surveillance: The carriers should be kept under

surveillance. They should be prevented from

handling food, milk or water for others.

v) Health education: Health education regarding

washing of hands with soap, after defecation or

urination and before preparing food is an

essential element.

In short the management of carriers continues to be

an unsolved problem. This is the crux of the problem,

in the elimination of typhoid fever.

Control of Sanitation:

Protection and purification of drinking water

supplies, improvement of basic sanitation, and

promotion of food hygiene are essential measures to

interrupt transmission of typhoid fever. For

instance, typhoid fever is never a major problem

where there is a clean domestic water supply.

Sanitary measures not followed by health education

may produce only temporary results. However, when

sanitation is combined with health education, the

effects tend to be cumulative, resulting in a steady

reduction of typhoid morbidity (Dutta et al., 2001).

Immunization:

While ultimately, control of typhoid fever must

take the form of improved sanitation and domestic and

personal hygiene; these are long-term objectives in

many developing countries. A complementary approach

to prevention is immunization, which is the only

specific preventive measure, likely to yield the

highest benefit. Immunization against typhoid does

not give 100 per cent protection, but it definitely

lowers both the incidence and seriousness of the

infection (Fraser et al., 2007). It can be given at any

age upwards of two years. It is recommended to: those

living in endemic areas, household contacts, groups

at risk of infection such as school children and

hospital staff, travellers proceeding to endemic

areas, and those attending melas and yatras.

Anti-typhoid Vaccines:

A vaccine against typhoid fever was developed

during World War II by Ralph Walter Graystone Wyckoff

(Dutta et al., 2001). There are two vaccines currently

recommended by the World Health Organization for the

prevention of typhoid: these are the live, oral Ty21a

vaccine (sold as ''Vivotif Berna'') and the

injectable Typhoid polysaccharide vaccine (sold as

''Typhim Vi'' by Sanofi Pasteur and ''Typherix'' by

GlaxoSmithKline). Both are between 50% to 80%

protective and are recommended for travellers to

areas where typhoid is endemic (Cooke et al., 2006).

Boosters are recommended every 5 years for the oral

vaccine and every 2 years for the inject-able form.

There exists an older killed whole-cell vaccine

that is still used in countries where the newer

preparations are not available, but this vaccine is

no longer recommended for use, because it has a

higher rate of side effects (mainly pain and

inflammation at the site of the injection).

1.2 ACQUIRED IMMUNODEFICIENCY SYNDROME (AIDS)

Acquired Immunodeficiency Syndrome (AIDS) is a

disease of the human immune system caused by

infection with human immunodeficiency virus (HIV)

(Sepkowitz, 2001). During the initial infection, a

person may experience a brief period of influenza-

like illness. This is typically followed by a

prolonged period without symptoms. As the illness

progresses, it interferes more and more with the

immune system, making the person much more likely to

get infections, including opportunistic infections

and tumours that do not that do not usually affect

people who have working immune systems (Sepkowitz,

2001).

1.2.1 EPIDEMIOLOGY OF AIDS

HIV/AIDS is a global pandemic (Sepkowitz, 2001).

As of 2011 approximately 34 million people have HIV

worldwide (Gallo, 2006). Of these, approximately

17.2 million are men, 16.8 million are women and

3.4 million are less than 15 years old (Gallo, 2006).

There were about 1.8 million deaths from AIDS in

2010, down from 2.2 million in 2005 (Gallo, 2006).

Sub-Saharan Africa is the region most affected.

In 2010, an estimated 68% (22.9 million) of all HIV

cases and 66% of all deaths (1.2 million) occurred in

this region (Kallings, 2008). This means that about

5% of the adult populations are infected (Vogel et al.,

2010). Here in contrast to other regions women

compose nearly 60% of cases (Kallings, 2008). South

Africa has the largest population of people with HIV

of any country in the world at 5.9 million (Blankson,

2010). Nigeria ranks 17 in the world in HIV infection

rates according to CIA world facts book in 2009 and

300, 000 infected with HIV/AIDS in Akwa Ibom state.

South and South East Asia (a region with about 2

billion people as of 2010, over 30% of the global

population) has an estimated 4 million cases (12% of

all people living with HIV), with about 250,000

deaths in 2010 (Kalish et al., 2005). Approximately

2.5 million of these cases are in India, where

however the prevalence is only about 0.3% (somewhat

higher than that found in Western and Central Europe

or Canada) (Gallo, 2006). Prevalence is lowest in

East Asia at 0.1% (Vogel, Schwarze-zander, Wasmuth,

Spengler, Saverbruch and Rockstroh, 2010).

In 2008 approximately 1.2 million people in the

United States had HIV; 20% did not realize that they

were infected (Vogel et al., 2010). It resulted in about

17,500 deaths (Vogel et al., 2010). In the United

Kingdom, as of 2009, there were approximately 86,500

cases and 516 deaths (Blankson, 2010). In Canada as

of 2008 there were about 65,000 cases and 53 deaths

(Kalish, Wolfe, Ndongmo, McNicholl and Rubbins, 2005).

Since AIDS was first recognized in 1981 and 2009 it

has led to nearly 30 million deaths (Goodier and

Kazazian, 2008).

1.2.2 CLINICAL FEATURES

The clinical features of HIV infection have been

classified into four broad categories (Dosekun and

Fox, 2010): initial infection with the virus and

development of antibodies; asymptomatic carrier

state; AIDS-related complex (ARC); and AIDS

Initial Infection:

Except for a generally mild illness (fever, sore

throat and rash) which about 70 per cent of people

experience a few weeks after initial infection with

the virus, most HIV-infected people have no symptoms

for the first five years or so. They look healthy and

feel well although right from the start they can

transmit the virus to others. Once infected, people

are infected for life. Scientist has not found as

yet, a way of curing them, or making them un-

infectious to others (CDC, 1982).

HIV antibodies usually take between 2 to 12 weeks

to appear in the blood-stream, though they have been

known to take longer. The period before antibodies

are produced is the ‘window period’ during which,

although the person is particularly infectious

because of the high concentration of virus in the

blood, he will test negative on the standard antibody

blood test.

Asymptomatic Carrier State:

Infected people have antibodies, but no overt

signs of disease, except persistent generalized

lymphadenopathy. It is not clear how long the

asymptomatic carrier state lasts.

AIDS-Related Complex:

A person with ARC has illnesses caused by damage

to the immune system, but without the opportunistic

infections and cancers associated with AIDS, they may

exhibit one or more of the following clinical signs;

unexplained diarrhoea lasting longer than a month,

fatigue, malaise, loss of more than 10 per cent body

weight, fever, night sweats or other milder

opportunistic infections such as oral thrush,

generalized lymphadenopathy or enlarged spleen.

Patients from high risk groups who have two or more

of these manifestations (typically including

generalized lymphadenopathy), and who have a

decreased number of T- helper lymphocytes are

considered to have AIDS-related complex, subsequently

develop AIDS (Dosekun and Fox, 2010).

AIDS:

AIDS is the end stage of HIV infection. A number

of opportunistic infections commonly occur at this

stage and/or cancers that occur in people with

otherwise unexplained defects in immunity. Death is

due to uncontrolled or untreatable infection.

Tuberculosis and Kaposi Sarcoma are usually seen

relatively early. Serious fungal infections such as

Candida oesophagitis, Cryptococcus meningitis and penicillosis,

and parasitic infections such as Pneumocystis carinni

pnuemonia Toxoplasma gondii encephalitis tend to occur,

when T-helper cell count have dropped to around 100.

People whose counts are below 50 have the late

opportunistic infections such as cytomegaloviral

retinitis (Templeton, Millett and Grulich, 2010).

1.2.3 TRANSMISSION

The causative virus is transmitted from person-to-

person, most frequently through sexual activity. The

basic modes of transmission are (Templeton et al., 2010):

a)Sexual transmission

AIDS is first and foremost a sexually transmitted

disease. Any vaginal, anal or oral sex can spread

AIDS. Every single act of unprotected intercourse

with an HIV-infected person exposes the uninfected

partner to the risk of infection. The size of the

risk is affected by a number of factors, including

the presence of STD, the sex and age of the

uninfected partner, the type of sexual act, the stage

of illness of the infected partner, and the virulence

of the HIV strain involved.

Anal intercourse carries a higher risk of

transmission than vaginal intercourse because it is

more likely to injure tissue of the receptive

partner. For all forms of sex, the risk of

transmission is greater where there are abrasions of

the skin or mucous membrane. For vaginal sex the risk

is greater when the woman is menstruating.

b)Blood contact:

AIDS is also transmitted by contaminated blood-

transfusion of whole blood cells, platelets and

factor VIII and IX derived from human plasma. There

is no evidence that transmission ever occurred

through blood products such as albumin,

immunoglobulins or hepatitis vaccines that meet WHO

requirements. Contaminated blood is highly infective

when introduced in large quantities directly into the

blood stream. The risk of contracting HIV infection

from transfusion of a unit infected blood is

estimated to be over 95 per cent. Since the

likelihood of HIV transmission through blood depends

on the ‘dose’ of virus injected, the risk of getting

infected through a contaminated needle, syringe or

any other skin-piercing instrument is very much lower

than with transfusion (Goodier and Kazazian, 2008).

c)Maternal-foetal transmission:

Mother-to-child transmission: HIV can pass from an

infected mother to her foetus, through the placenta

or to her infant during delivery or by breast-

feeding. Transmission during the peripartum period

accounts for one-third to two-thirds of overall

numbers infected, depending on whether breast-feeding

transmission occurs or not, and this period has,

therefore, become a focus of prevention efforts. The

risk of infection is higher if the mother is newly

infected, or if she has already developed AIDS (Park,

2011).

There is no evidence that HIV is transmitted

through mosquitoes or any other insect, casual social

contact with infected persons including within

households, or by food or water. There is no evidence

of spread to health care workers in their

professional contact with people with AIDS (Dosekun

and Fox, 2010).

1.2.4 PREVENTION AND CONTROL

1.Prevention:

a)Education:

Until a vaccine or cure is found, the only means

at present available is health education to enable

people to make life-saving choices (e.g. avoiding

indiscriminate sex, using condoms). There is however,

no guarantee that the use of condoms will give full

protection. One should also avoid the use of shared

razors and toothbrushes. Intravenous drug users

should be informed that the sharing of needles and

syringes involves special risk. Women suffering from

AIDS or who are at high risk of infection should

avoid becoming pregnant, since infection can be

transmitted to the unborn or newborn. Educational

material and guidelines for prevention should be made

widely available. All mass media channels should be

involved in educating the people on AIDS, its nature,

transmission and prevention; these include

international travelers (CDC, 1982).

b)Prevention of blood-borne HIV transmission:

People in high-risk groups should be urged to

refrain from donating blood, body organs, sperm or

other tissues. All blood should be screened for HIV 1

and HIV 2 before transfusion. Transmission of

infection from haemophiliacs can be reduced by

introducing heat treatment of factors VIII and IX.

Strict sterilization practices should be ensured in

hospitals and clinics. Pre-sterilized disposable

syringes and needles should be used as far as

possible. One should avoid injections unless they are

absolutely necessary (Templeton et al., 2010).

2.Antiretroviral treatment:

At present there is no vaccine or cure for

treatment of HIV infection/AIDS. However, the

development of drugs that suppress the HIV infection

itself rather than its complications has been

important development. This antiviral chemotherapy,

while not a cure, has proved to be useful in

prolonging the life of severely ill patients (Sharp

and Hahn, 2011).

The availability of agents that alone and in

combination suppress HIV replication has had a

profound impact on the natural history of HIV

infection. Patients who achieve excellent suppression

of HIV generally have stabilization or improvement of

their clinical course which results from partial

immunologic reconstitution and a subsequent decrease

in complications of immunosuppression. Concept about

the timing of such therapy has changed considerably.

Monitoring the efficacy of ART

Efficacy is monitored by (Vogel et al., 2010);

a)Clinical improvement: gain in body weight,

decrease in occurrence and severity of HIV-

related diseases (infections and malignancies),

b)Increase in total lymphocyte count,

c)Improvement in biological markers of HIV (when

available); CD4 + T-lymphocyte counts and plasma

HIV RNA levels.

3.Specific prophylaxis

Kalish et al. (2005) posited that until more

effective antiviral therapy becomes available, the

main aim of existing therapies will be to treat the

manifestations of AIDS. Primary prophylaxis against

Pneumocystis carinni pneumonia should be offered to

patients with CD4 count below 200 cells/µL. The

regimens available are trimethoprim-sulfamethoxazole,

aerosolized pentamidine and dapsone. Patients who

develop Pneumocystis carinni infection on a particular

prophylactic regimen should be switched to the other

drug or should receive a combination regimen.

4.Primary health care:

Dueof its wide ranging health implications, AIDS

touches all aspects of primary health care, including

mother and child health, family planning and

education. It is important, therefore, that AIDS

control programmes are not developed in isolation.

Integration into country’s primary health care system

is essential (Blankson, 2010).

SUMMARY

Infectious diseases will last as long as humanity

itself, therefore it is necessary to employ control

and preventive measures to curtail the increasing

morbidity and mortality rates of communicable

diseases in our immediate community like the Annang

community. Long-lasting treatment measures should be

advocated for opportunistic and exposed individuals

in order to avoid new case and epidemics.

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