Fighting infections

Fighting disease: In the first �eca�es after the intr��ucti�n �f antibi�tics,� there �as �i�es�rea� ��timism that the fi�ht a�ainst infecti�us �isease c�ul� be ��n. This early a�vert f�r �enicillin �as tar�ete� at W�rl� War II servicemen. (Picture: Wiki�e�ia.) F�r a fe� �eca�es,� ar�un� the mi��le �f the 20th century,� there �as �i�es�rea� ��timism that science c�ul� �in the fi�ht a�ainst infecti�us �iseases,� re�uce their s�rea� an� the �ama�e they �� t� the infecte�,� an� even era�icate s�me. Penicillin became available in the 1940s an�,� in the �eca�es after that,� m�re an� m�re antibi�tics �ere �evel��e� an� successfully use� in the fi�ht a�ainst �isease. On a se�arate fr�nt,� the successful era�icati�n �f small��x thr�u�h vaccinati�n sh��e� that �isease threats can be eliminate�. H��ever,� by the en� �f the 20th century,� small��x remaine� the �nly exam�le �f era�icati�n,� ne� �ath��ens emer�e�,� an� many �l� f�es,� such as tubercul�sis,� sa� a resur�ence. Furtherm�re,� scientists f�un� that bacterial �ath��ens �evel�� resistance a�ainst existin� antibi�tics as fast as the �harma in�ustry can �evel�� ne� �nes. This threat �i�n’t arise entirely fr�m natural causes. It became clear in the 1990s that the �i�es�rea� misuse an� �veruse �f antibi�tics,� such as their blanket use in a�riculture,� create� the envir�nments �here micr�bial strains are enc�ura�e� t� �ass ar�un� existin� resistance traits an� even t� �evel�� ne� �nes. F�r a �hile,� the in�ustry trie� t� kee� u� the race an� �evel��e� ne� antibi�tics,� but in recent years,� the �i�eline �rie� u�. As Laura Pi���ck fr�m the Antimicr�bial A�ents Research Gr�u� at the University �f Birmin�ham ��inte� �ut in a c�mment f�r The Lancet last year,� n� m�re than three antibacterial a�ents �ere a��r�ve� since 2008,� c�m�are� �ith 16 in the years 1983 t� 1987. Pi���ck lists several reas�ns f�r this �ecline in �ru� �evel��ment: “mer�ers bet�een �harmaceutical c�m�anies have re�uce� the number an� �iversity �f �ru�-�isc�very teams,� an� many c�m�anies have �ith�ra�n fr�m �evel��ment �f antibacterial �ru�s” she �rites. She als� ��ints �ut that initial h��es f�r �en�mics t� yiel� ne� tar�ets f�r antibacterial �ru�s have been �isa���inte�. Finally,� she ��ints �ut that f�r c�m�anies �evel��in� antibi�tics “the return �n investment is l�� because antibi�tics,� unlike many �ru�s,� are usually use� f�r sh�rt-term c�urses �f treatment (5–7 �ays).” T� im�r�ve the ec�n�mic viability �f such �ru�s she su��ests they mi�ht be s�l� at hi�her �rices,� es�ecially c�nsi�erin� the years �f life they save in c�m�aris�n t� m�re ex�ensive but less efficient cancer �ru�s. Alternatively,� ��vernments an� aca�emic instituti�ns c�ul� take u� m�re �f the research an� �evel��ment ��rk. “This is the �ara��x �e fin� �urselves in,�” says Pi���ck,� “at the very time �e have the kn��le��e t� �esi�n ne� an� effective antibi�tics,� fe� �harmaceutical c�m�anies �ish t� �evel�� them. In all likelih���,� �isc�very an� early research �ill be by aca�emic researchers an� clinical research an� �evel��ment by the c�mmercial sect�r. T� �et this m��el ��rkin� effectively t� meet the bacterial infecti�n challen�es,� a ne� fun�in� m��el is require�.” What �as �nce the sin�le bi��est bacterial threat in in�ustrialise� c�untries,� the methicillin-resistant strains �f Staphylococcus aureus (MRSA),� seems t� have subsi�e� s�me�hat in the last fe� years. In 2011,� the number �f rec�r�e� cases �f MRSA infecti�ns fell t� a rec�r� l��. This si�nificant success is the result �f the attenti�n hea�e� �n MRSA an� similar Gram-��sitive bacteria �n all levels fr�m �ru� �evel��ment thr�u�h t� clinical �ractice. But in the meantime,� Pi���ck �ia�n�ses,� there is a “�enuine rarity �f a�ents t� treat infecti�ns cause� by Gram-ne�ative bacteria.” Gram-ne�ative bacteria inclu�e E. coli an� the �neum�nia �ath��en Klebsiella pneumoniae. Resistance traits kn��n as NDM-1 an� KPC,� res�ectively,� make these bacteria resistant t� carba�enem antibi�tics an� c�ul� bec�me a threat in the future. As the �utbreak �f a �ath��enic E. coli strain in Germany in June 2011 has �em�nstrate� �nce m�re,� �an�er�us infecti�ns can c�me a��arently �ut �f n��here an� �reak hav�c even bef�re the me�ical ex�erts are able t� ��rk �ut �hat is ��in� �n. The British S�ciety f�r Antimicr�bial Chem�thera�y has recently launche� a �l�bal initiative calle� Antibi�tic Acti�n (htt�:// antibi�tic-acti�n.c�m/),� �hich aims at “Inf�rmin� all ab�ut the nee� f�r �isc�very,� �evel��ment an� a��r��riate use �f antibi�tic a�ents.”