Hi Ella, thanks for join­ing us. What melioi­do­sis symp­toms should nurs­es be look­ing for?

Melioi­do­sis has wide-rang­ing clin­i­cal man­i­fes­ta­tions. Pneu­mo­nia is the most com­mon pre­sen­ta­tion, and symp­toms may include fever, short­ness of breath, cough, puru­lent spu­tum pro­duc­tion, and pleu­rit­ic chest pain.

Many patients have blood­stream infec­tion, and may have sep­sis or sep­tic shock.

Any organ sys­tem in the body can be involved. Pro­sta­t­ic abscess is com­mon in men, pre­sent­ing with fever and uri­nary reten­tion. B. pseudo­ma­llei can cause abscess­es in the liv­er or spleen, and bone and joint infec­tions. Encephalomyelitis is a rare but poten­tial­ly dev­as­tat­ing presentation. 

Some cas­es have a chron­ic pre­sen­ta­tion, with cough, weight loss, and a cav­i­tary lung lesion mim­ic­k­ing tuber­cu­lo­sis. Oth­ers have a chron­ic non-heal­ing skin ulcer. Such patients may be sys­tem­i­cal­ly well. 

Melioi­do­sis should be con­sid­ered a pos­si­ble diag­no­sis in cas­es of patients with sep­sis, par­tic­u­lar­ly dur­ing the wet sea­son, and par­tic­u­lar­ly in patients with risk factors.

Which risk fac­tors exactly?

Through the Dar­win Prospec­tive Melioi­do­sis Study (DPMS), we’ve iden­ti­fied some key risk fac­tors, includ­ing dia­betes, haz­ardous alco­hol con­sump­tion, chron­ic kid­ney dis­ease, and immuno­sup­pres­sion, for exam­ple can­cer chemotherapy.

From the research, it emerged that nine patients con­tract­ed melioi­do­sis because of Kather­ine Riv­er flood­ing in Jan­u­ary 1998. Of the nine, five recalled an inoc­u­lat­ing injury. Patient his­to­ry seems high­ly rel­e­vant as well?

We think most cas­es are acquired either by per­cu­ta­neous inoc­u­la­tion through skin trau­ma, or by inhala­tion of aerosolised bac­te­ria dur­ing severe weath­er events. It’s not uncom­mon for melioi­do­sis patients to recall a par­tic­u­lar event, such as an injury sus­tained while gar­den­ing, or being caught in a severe storm. 

Some peo­ple may have occu­pa­tion­al expo­sures through their work out­doors. Oth­ers may under­take recre­ation­al activ­i­ties that increase their expo­sure. Most peo­ple exposed to B. pseudo­ma­llei do not get melioi­do­sis – it is those with comor­bidi­ties affect­ing the immune sys­tem who are most at risk.

What sort of incu­ba­tion peri­od are we deal­ing with?

Based on the time between inoc­u­lat­ing injury and symp­tom onset for patients in the DPMS, the incu­ba­tion peri­od is between one to 21 days.

How is melioi­do­sis diagnosed?

Diag­no­sis requires cul­ture of B. pseudo­ma­llei from clin­i­cal spec­i­mens. We rec­om­mend col­lect­ing blood cul­tures, ide­al­ly two sets from dif­fer­ent sites at dif­fer­ent times, throat and rec­tal swabs in Ashdown’s medi­um if that’s avail­able, and oth­er spec­i­mens depend­ing on the site of infec­tion; for exam­ple, spu­tum, urine, skin swabs, and pus spec­i­mens. If melioi­do­sis is sus­pect­ed or there are par­tic­u­lar envi­ron­men­tal expo­sures, please doc­u­ment this on the pathol­o­gy request form as it will inform spec­i­men pro­cess­ing in the laboratory.

Melioi­do­sis is under­stood to be asso­ci­at­ed with severe weath­er events. What role will cli­mate change play in the spread of melioidosis?

In the Top End, the vast major­i­ty of cas­es occur dur­ing the wet sea­son from Novem­ber to April. 

Spikes in cas­es, as seen in the Kather­ine study, can occur fol­low­ing severe weath­er events such as cyclones, high rain­fall, and high winds. 

It is pre­dict­ed that as the cli­mate changes there will be an increase in the fre­quen­cy and sever­i­ty of extreme weath­er events such as cyclones, and it is like­ly that melioi­do­sis cas­es will increase in asso­ci­a­tion those changes.

Is there also a chance it will head fur­ther south, as weath­er pat­terns shift? 

Yes. The regions of its endemic­i­ty are pre­dict­ed to expand fur­ther south in Australia. 

How far south has it been found up until now?

There have been occa­sion­al cas­es report­ed in Cen­tral Aus­tralia and in South­east Queens­land, in asso­ci­a­tion with peri­ods of heavy rainfall.

What sort of health pro­mo­tion mes­sages should remote clin­ics focus on?

Health pro­mo­tion should tar­get those at great­est risk of becom­ing unwell with melioi­do­sis – indi­vid­u­als with dia­betes, haz­ardous alco­hol con­sump­tion, chron­ic kid­ney dis­ease, or oth­er immunosuppression.

Dur­ing the wet sea­son it is rec­om­mend­ed that peo­ple wear shoes, and gloves while gar­den­ing. Peo­ple with risk fac­tors should stay indoors dur­ing storms. This advice could be incor­po­rat­ed into a health check, for example.

Cul­tur­al con­sid­er­a­tions and social dis­ad­van­tage may mean it is less like­ly for pro­tec­tive footwear to be worn in some remote areas. There’s clear­ly some com­plex­i­ty here?

More work needs to be done to under­stand the most effec­tive ways of pre­vent­ing melioi­do­sis. It is like­ly that bar­ri­ers exist to enact­ing the pre­ven­tive mea­sures described above. Some peo­ple may have hous­ing inse­cu­ri­ty, which may mean sleep­ing rough and increased B. pseudo­ma­llei expo­sure – address­ing high home­less­ness rates in remote north­ern Aus­tralia is vital. Treat­ment and pre­ven­tion of dia­betes, chron­ic kid­ney dis­ease, and haz­ardous alco­hol con­sump­tion are also very impor­tant. All of this requires ade­quate fund­ing and com­mu­ni­ty partnerships.

What does treat­ment look like, and what’s the role of the remote area nurse in all of this?

Treat­ment includes an inten­sive phase of at least two weeks of intra­venous antibi­otics, and an erad­i­ca­tion phase of at least three months of oral antibi­otics. The dura­tion of each phase depends on the sever­i­ty of the infec­tion and the body site that is involved, with treat­ment deci­sions made in con­sul­ta­tion with the infec­tious dis­eases team. 

Nurs­ing staff play a key role. Remote area nurs­es recog­nise sep­sis, col­lect appro­pri­ate spec­i­mens for cul­ture, and start man­age­ment with flu­ids and empir­ic sep­sis antibi­otics (as out­lined in the CARPA Stan­dard Treat­ment Man­u­al) – all of that can be life-saving. 

Like­wise once a patient returns to a com­mu­ni­ty, remote area nurs­es play an impor­tant role in sup­port­ing that per­son through the erad­i­ca­tion phase of treat­ment so that they don’t have relapse of infection.

Hos­pi­tal-based nurs­es also play an extreme­ly impor­tant role. In the Emer­gency Depart­ment, the Inten­sive Care Unit, and on the wards, they pro­vide expert man­age­ment of sep­sis. The Hos­pi­tal In The Home nurs­es play a key role in sup­port­ing com­ple­tion of intra­venous treatment.

How impor­tant is fast treatment?

It can take 48 hours for B. pseudo­ma­llei to be iso­lat­ed from clin­i­cal spec­i­mens and for the diag­no­sis of melioi­do­sis to be made. If some­one is crit­i­cal­ly unwell, there may not be time to wait for that infor­ma­tion. The rec­om­mend­ed antibi­otics out­lined in Top End sep­sis guide­lines includ­ing the CARPA Stan­dard Treat­ment Man­u­al have activ­i­ty against B. pseudomallei.

Any take­away mes­sages for our readers?

I’d just like to thank all the nurs­es involved with the care of melioi­do­sis patients in the Top End – you do a won­der­ful job!